That said I kinda get the social media obsession, that was college for me and I was all in on the facebook parasocial queues (not liking someone's post that they KNOW you saw was an offense, and other crazy shit). For me it was ultimately a function of not having anything better to do. High school is supermax prison in terms of options, college is like minimum security prison, it's not really until you hit the realization that your decisions have actual weight in your life and you aren't just going to be pushed along by external forces that you start to grow out of that. High school ends and eventually becomes irrelevant, but good luck explaining that to a teenager.
I'd argue the income question is also part of the problem, the "mail room to executive" pipeline, if it ever really existed, has been completely broken. As you say, it used to be that person working the McDonalds drive through might be something big some day. Nowadays that's 100% assured to not be the case, McDonalds drive through is a dead-end job you do to stay alive until you can trade up to a different career path.
Can you expand on how you see these two statements as different conceptually? At least for folks in my generation, I don't think anyone harbored delusions that they were going to make it big by working at McDonald's, but it was seen as a way to get basic work experience and the benefit of a wage while you worked towards something different. The "mail room to executive" pipeline was always a fantasy, as far as I'm concerned, just due to basic math, there's a lot more mail room clerks than executives, so it in all probability won't happen to you. On the flip side, working a summer job provides you a pathway to pay for entertainment and a modicum of freedom so you can explore the world and figure out what you actually want to do. At least that's how it was seen when I was a teenager.
Nowadays the options for standard middle-class success are a lot more constricted. There is much less "freedom" and "exploring" unless you're wealthy, working at McDonalds will just get you an ultimately meaningless amount of money and experience that no one values, while sucking up your time. Even when I was in high school there was no time for "exploration" outside of academics if you wanted a positive outcome. You were either on the AP/honors track and going to college to be a "success", or you had a job/took normal classes and either couldn't afford college or were just coasting into mediocrity. I imagine it's gotten even more stark since I graduated, given prevailing economic circumstances.
I'd say the desire to be an influencer/streamer is also partially the result of that. Sure statistically most influencers/streamers don't make much, but there's at least the potential of freedom/success that doesn't exist with a McDonalds job, directly or indirectly; and the barrier to entry is low. It would be like if everyone's parents bought them a guitar/drum set and there was a social hierarchy based on being a rock star.
If I can be so bold as to link it into larger trends, one thread I've noticed is that in previous generations' countercultures, whether it was the hippies in the 60s/70s or grungy Xers in the 90s, there was an underlying assumption that the American Dream was vanity. That you didn't need all of that stuff and could "drop out", calling someone a "sellout" was a serious insult. You could always find a way to "get by" even if you weren't living large. Because during those times where the income/cost of living disparity wasn't so large, you probably could. Don't worry about prosperity, go become an assistant manager at Staples and spend your time on what really matters! Nowadays economics don't support that, so we have "hustle culture", where you're expected to "grind", and that's the superficially "cool" thing to do. Even if you're just hocking bullshit, make that money! Given the limited options available to high school students, it follows that being an influence/streamer, something they can literally do on their phone, is the only universally attractive objective.
That's the source of fear I mentioned earlier, being sold this idea that the only way to get a job is to go to college and if you don't 100% focus on college you won't make it. But there is nothing in the data to suggest that idea actually panned out. All signs point to young adults having a much harder time moving up because they didn't work in their youth to gain the experience necessary to navigate the waters of the economy.
So, if they are seriously trying to become an influencer, accepting any time commitment that doesn't further that objective and removes them from that social sphere effectively ends any chances of it happening. Additionally to the above, my teenager has admitted to me that she knows that influencers are time-limited with their success, it's something that really only happens when you're young, cool, and pretty, and shortly after you have a fall-off. They'd rather make the attempt while they're young and have a lot of anxiety around not doing it, and falling into mediocrity.
My generation was never exposed to that, we were exposed to Tommy the lawyer who got his start working the stock room at the hardware store and now drives a Porsche. The type of "instant" fame and money that kids get exposed to now just wasn't even in the realm of possibility for my generation, except perhaps sports stars. Even though the number of people who "make it" vs those who try is vanishingly small, a lot of folks in Gen Z seem to think being an influencer or a similar role is the primary career path they want to try for, and unlike something like being a sports star, it's less limited by outside influences and requires less genetic talent. Anyone could, possibly, be an influencer, even though very few people actually will become one.
Now, taking that job is no longer seen as a stepping stone, it's seen as giving up and admitting to yourself and the world you won't be able to hack it online. It's truly remarkable if you observe high schoolers, girls especially, these days and how much of their life is spent online vs with those directly around them. Social media is not just entertainment, it's one of the most important things in their lives, and their presence there is seen as a determinant for their future. This is a very different social zeitgeist than my generation grew up with, and I'm a Millennial, grew up with Internet and computers, but prior to the dawn of social media.
This isn't an economic issue in that sense, then, it's a social issue, a rejection of the type of work that most people in the US started with when they were that age. A drive through worker at McDonald's makes nearly $37k/yr if they work full-time at the starting wage where I reside now. That's more than many professionals made when they started their careers when I was a teenager, and it's more than double what I made starting as a shelf-stocker /inflation-adjusted/. It's not that the job doesn't pay enough to attract people who are starting out, it's that those people see it as a serious social faux pas to be caught working that type of job, it's an admission and acceptance of failure, rather than an admirable place to begin.