You can't optimize for knowing better than the buyer themselves. If they bought, you have to assume they found the best deal for them considering all the tradeoffs they care about. And that if a business is willing to pay more for that click than another, it's more likely to lead to a sale and therefore was the best deal, not the worst.

Sure, there are many situations where users make mistakes and do some bad deal. But there always will be, that's not a solvable problem. Is it not the nirvana fallacy to describe the potential for suboptimal outcomes as an issue? Search engines and AI are great tools to help users avoid exactly that outcome.