That’s true when they pay out. It’s supposedly hard to get to get them to actually pay.
They say they pay out 55% of ad revenue per video and 55% of subscription revenue.
Assuming 10% of video creators have successfully set up monetization (I made up that number), then they are only paying out 5.5% of ad revenue, since (as far as I know) the unclaimed ad revenue is not pooled and the distributed proportionately to other accounts.
It’s unclear if they put YouTube premium revenue in per-creator buckets in the same way as they do ad revenue. If so, then they would only be paying out 5.5% of subscription revenue in my 10% example. If, on the other hand, subscription revenue is split amongst just the monetized creators that you personally watch, then they would be paying the 55% their marketing department likes to brag about.
I haven’t been able to figure out which way they do the accounting.
However, as of 2021, over their service lifetime, they paid $30B to creators. Their 2022 revenue was $29B
So, they’re definitely keeping the vast majority of the combined ad and subscription money that comes in the front door (or revenue exploded in 2022).