Who needs that in their life? If your product can't stand on its own merit and you need to bathe swaths of the general public with nonsense to sell anything then maybe your product deserves to fail?
I'd rather a service be funded by ads, because if not, they'll have to find some other way to make money, which could include:
Paywalling - I won't use it then.
Selling your personal information egregiously - I don't mind when a company has the information I give them, but if they're relying on selling it as their primary income, it's probably going to lead to something shady.
Cryptocurrency mining - I don't want my computer to heat up while I'm trying to watch YouTube videos, as I often do that to let my computer cool down between games.