Yes, this. With programs like skimlinks providing affiliate links for pretty much every single retailer, I'm not even sure how they would review a product that they don't get a kickback from.
I guess I'm just generically distrustful of reviews in general. Companies can give bad reviews just like normal users give terrible reviews. I don't think I've ever seen a review system that you didn't have to take with a big grain of salt.
Is there any evidence to suggest Wirecutter has refused to rate an item due to lack of affiliate links?