That is near impossible to enforce and manage.I agree with ya dude, but I think the recent 5 star reviews should be held to the same standards if 1 star reviews are being removed. Hell... all reviews before this update should get a N/A while we're at it. They don't reflect the current state of the game.
There will be examples of devs that start out bad and then improve or the other way around.
While remakes/tech updates like this is quite easy to spot when they are released it muddles everything when you start removing reviews, there will always be a grey area how far back and what reviews should be applicable.
In my mind there you should have to write what version you review, that would make it a bit more clear.