Facebook banned cryptocurrency ads because there were many scamcoins and fraud. Of course, Bitcoin and other legit cryptocurrencies don't deserve to be banned because of those frauds and I think the people at Facebook realised that and I'm glad they made that checking system. I hope all other sites will adopt this system and allow Bitcoin advertising.
Yeah, of course verifying each project to make sure it's legit spend some resources and takes some work. But in can be really good for both the company and Bitcoin/Cryptocurrencies.
Scams exists anywhere though, so what is the surprise? - The difference is that a lot of businesses operating in crypto are not formally registered and for that reason they are not can't be legally enforced to comply with anything.
We'll see in the future. But taxes in Bitcoin are pretty good precisely because the governments start to accept it which encourages companies to do everything legally, register and offer a good service.