Well, something have to buy into it first, and decide to make a review of some sorts.
If the flood gate open, the more games are released, the less reviewed they are.
They won't sell well In those cases where there is a lot of uncertainty. Not until they catch on. There will be some that will pay for them and regret it, but that's always been the case and always will be.
It's not going to bring the market crashing down like it did in the 80s when people were buying them off of the shelves with none of the advantages of information access that we have today. By and large shovelware fails today because people know better.
I agree that if you only target well known franchises you don't risk much, but there is the problem with competent small developers unable to get the fame they deserve, and you missing the game exactly made for you.
It will be competitive, but I view that overall as a good thing for the consumers.