Circa 2010, as I was finishing up my BS in CS, one of my professors asked me to have a meeting in his office. He was trying to recruit me into a graduate program under him, since he liked my performance in his class. I said I wasn't very interested, since I wanted to make things people will actually use. His response was there was a team in Utah that helped make part of the USB spec the decade previous. I was attending the University of Minnesota.
Yeah, no thanks.
Source: I’ve worked on both.
Those aren't the only two options and even they were, it isn't always true.
My guess is that if you want to be paid full-time to work on USB, you'll probably find more (and better-paid) positions in industry.
I had the same feeling!
And as it turns out, many of the skills are transferable: https://twitter.com/mizzao/status/1505529213612609536
From a personal perspective I don't regret my PhD, though it was charity funded so it was topped up to be around £20 000 instead of the usual £14000ish per year. It was an opportunity to engage with a small group of experts in research that was engaging and of use to the wider world, and present it internationally. I also tried to start a start-up during this time, but the underlying idea failed to pass preliminary trials (I work in healthcare). So the two are not mutually exclusive.
People's experience tends to vary. I think a lot depends on how much you research the group and supervisors you will be working with beforehand, and how much you engage them in the research you do.
I was lucky enough to get involved in the web very early (1992) and present papers at the first few web conferences - though that wasn’t my day job.
Edit: I worked on a couple of EU Esprit 2 projects.
I left to co-found a start-up - never regretted it as I was "hyper cynical" (a direct quote from a colleague) about the whole academic world and how easy it was to play the "publish or perish" game.
I like building stuff that people use, not writing papers that mostly went unread.