Don't forget to factor in that evergreen content will continuously bring in money, especially if you're funnelling in viewers from outside the YouTube algorithm. A video I made in 2014 is still the bulk of my YouTube income
> especially if you're funnelling in viewers from outside the YouTube algorithm
This is why a lot of people encourage youtubers to diversify away from ad-revenue. A youtuber that relies solely on ad-revenue is like a supplier with only one customer. They are at the complete mercy of the whims and competency of their single customer.
This is a large part of the reasoning behind patreon. Then there are people like CGP grey that diversify to podcasts, have patreon, sell merch and get paid-for promotions.
One thing that may be worth adding is that for Dave Jones in particular, he has other lines of income such as selling hardware (project kits, branded multimeters, T-shirts, etc) and ads on his popular webforum. The YouTube channel works as advertising for those businesses. So even if you don't make a good living off of the YouTube revenue, it may still make sense as a way of building a loyal customer base.
A lot of YouTubers also make a good chunk of their income on Patreon now as well.
With Patreon, it's more properly considered as just another payment processor: the hope is that you'll build a functioning business and use it to handle people's credit card interactions.
So while CGPGrey might be making $20k/video for the first video, anyone with a (say) $5/month cap that paid $5 for the first video now pays nothing towards any videos released later in the month, potentially dropping the income substantially as more and more spending caps are hit as the month rolls on.
On the other hand, YT is populated by people from different countries. $20/hour is not great in US or UK, but where I'm from that's about 10x the minimum wage and 3-4x the median wage. There's plenty of foreign creators on YT and for them that amount of money places them firmly in the top income bracket.
One day you are on page one and monetizing (I've been there), next day, page 5 and nothing (been there too).
Another guy I like to follow, Lord Karnage, has similar number of subscribers, but most of his videos get far fewer views, 6k-10k and he's got over 4,000 videos up. I've heard an interview with him about his business and tbh, it doesn't sound great. He'd make more money panhandling playing video games on a street corner.
On the other hand, Simon and Martina, 1.2 million subs, between 300k-400k views per video and 4 videos a month, seem to be living a decent middle class life in Seoul and then Tokyo. No idea how much money they make, but they've had employees in the past to help them with their video production. Some calculators seem to claim they're probably making something a bit north of $100k.
One of the things that I find really disturbing is that, every so often, google will just "change" the payment computation and suddenly people who were putting 50-60 hour weeks into youtubing to make a fairly minimal living are suddenly seeing their income cut by huge percentages. Eventually everybody will figure out what changed and things will settle down, but there's a few weeks seemingly every year, where my subscription feed will be full of people complaining or shutting down channels.