Advertising-based business models don’t work in digital spaces. There are too many incentives to try and abuse the system, which will inevitably break the supply and demand curve.
Some of this can be mitigated with closed systems where there can be a bit more trust between everyone involved. Direct advertiser and publisher relationships, for example, with no ad platform intermediary — but that has its own set of ethical problems.
But the key takeaway is, if you run a business that gets the majority of its revenue from ads, you should have already been thinking of ways to change that.