It's a nice idea and I can see it working in some cases.

I'll be the first to admit I don't know the specifics, but I imagine in some cases, it's economically prohibitive to lower the price by such an amount that it makes up for the uncertainty in a typical search algorithm.

Then your product is actually worse for the customer. It's nice that you want it to be better, but it's not in a meaningful way that you can't just handwave away. Risk carries a cost.

Another possibility would be for the marketplace to be better able to load information about your product so you could provide some more information and reduce that uncertainty. E.g. that you use different (better) materials in your construction. Or you could work with the marketplace to purchase or demonstrate some kind of insurance policy to mitigate support concerns. Basically allow those unknown pieces of information to be discoverable by search engines and the customer. If the market has more knowledge, then if you have a better product, it should organically rank better. Either way, ads do literally nothing to benefit the buyer since they provide zero information (actually they provide a negative piece of information: someone paid for you to see something, so you can assume it's not in your interest to see it).