Youtube probably has the technology to autoblock porn etc so I'm sure they will or can develop something similar. A human vetting the adds should be the least they do right now until they have the tech.
The only reason they are doing
that (porn filter) is to avoid a public outcry which would, you guessed it, damage their revenue.
People would still use YouTube even when it's full of scams, as evident today. So clearly (and sadly) there is no outcry to hit their bottom line. These guys only do stuff for their own pockets and not for their users.
Constantly advertising scams will also hurt their revenue if it's becomes popular opinion that YouTube is just a wild west of scams and scammers. The whole adpocalypse thing was spurred on by advertisers being worried about their adverts showing up on problematic content and even terrorist videos etc and withdrawing their ads and Youtube just went full overkill and into panic mode. I'm sure that will happen again and they will surely start facing legal consequences when people are continuing to lose money. It's not a good look for them at all and if they don't implement some safety standards they will soon be forced to.