The scale of data storage, transcoding compute, and bandwidth to run YouTube is staggering. I'm open to the idea that adblocking doesn't have much effect on a server just providing HTML and a few images, but YouTube's operating costs are (presumably, I haven't looked into it) staggering and absolutely incompatible with adblocking.
Businesses (in particular the literal biggest ad agency in the world) should know who they are partnering with. Not vetting the people they're allowing to place ads is at best negligent. The fact that the FBI warns people to use ad blockers to protect themselves from fraud (instead of anyone doing anything about it) is shameful. Someone either approved the scams or the system which allows these unvetted partners to operate. There should be a criminal investigation into how this came to be. Especially considering people have anecdotally said online that they've reported scam ads and received a reply that the ad was reviewed and determined to not violate policy (that may be Facebook, or both. In any case this applies to anyone). At that point they unambiguously have actual knowledge of and are a participant in the fraud. People at these ad companies should be looking at prison time if that is indeed happening.
I'm curious as to what the scam ads you mention actually are. I use an adblocker most of the time, and most of the adverts that I do see are annoying but fairly innocuous. Furniture, insurance, charter schools, social media apps, shitty mobile games, et cetera. I've seen plenty of slightly scummy adverts, but I can't recall seeing many that are really harmful or blatantly fraudulent. I'm curious to hear what adverts other people are seeing that are so outrageous.
Additionally, Google has a well known policy of allowing people to take out ads (which look exactly like a search result) for someone else's trademark (defeating the entire purpose of a trademark), and the FBI has a frequently referenced notice[2] to US citizens to be aware of fraud where scammers take out impersonating ads on "Internet search results" to e.g. lead people to the wrong site for financial institutions. It absolutely blows my mind that no one is prosecuted for participating in this.
[0] https://old.reddit.com/r/youtube/comments/18gjiqy/youtube_do...
[1] https://www.reddit.com/r/Scams/comments/1h6rdtj/massive_incr...