There is no tolerable amount of ads, because not only are they an awful experience, they explicitly drive user hostile growth and decisions in the future (ie enshitification).
I used to pay for YouTube to avoid ads, before I got sick of Google and refused to give them any more money. Now I use a pihole and a browser based adblocker, as well as 3rd party front ends, because fuck Google. I don’t give a shit if I’m denying them income.
If it we weren’t Google, I’d be ok with paying too. As it is, the content creators will have to get by with their individual sponsorships, rather than getting ad revenue from me.