Genuine question: Where are you getting this to be the general consensus?
It isn't critic reviews, as SV are the lowest rated mainline games in the series. It isn't Twitter, Reddit, or ResetEra, as those places are quite critical on the game. Era's stance is pretty obvious, and r/pokemon just did a poll that placed Gen 9 as second lowest in the series only above Gen 8.
So where is this general consensus coming from? Is it just based on sales numbers?
r/pokemon has never been positive ever since Dexit happened
However a variety of polls have had it high, people in dedicated communities all around the Internet. I see it on Serebii. I see it everywhere.