It's actually probably too high. Think about it from the ad buyers perspective. You spend $10K to get a million views on your ad, then 1% of people click on it, so 10k views on your target site, then if your product is amazing 10% of those people will engage by downloading or signing up or looking for it at a store or whatever, so now you're down to 1000 people that each have to give you $10 or you're losing money.

At these levels of engagement, which are optimistic, you probably want your per-user monetization to be hundreds of dollars, or at least have the potential to get there. That's why every ad is for some scam with huge profit potential. Subscription services, gambling games, loans, habit forming products, that kind of shit. Those are the only things that can justify the cost.

It's a marketplace so what happens is the scam products drive up the cost because their profit margin is so high. If youtube banned the scammers, average ad cost would go way down so there's a perverse incentive for youtube to ignore scammers.