He can act but that movie was beyond stupid. I'm convinced the only reason it did well with critics is exactly what you said - they were surprised he could actually act.
Good grief, another one I was going to mention that's already covered.
His movies are mostly bad, I think you and I might agree on that.
But the other aspect of it is that a lot of the people I knew who liked his early movies were just really shitty humans. So by association, I think that affected how I saw his movies. Just seemed like a magnet for terrible people and it was hard to separate those two things for me. Not to mention, the movies themselves were objectively somewhere between awful and just not that great, so I didn't feel like I was missing out much.
Oh, and I got "dragged" to that movie I Now Pronounce You Chuck & Larry IN THE THEATER. And that reasserted everything I already knew to be true about Adam Sandler movies.
IMO, he has been playing the same over-grown man-child of a character in every movie for 20 years (with exceptions).
Also Happy Madison studios wrote Dana Carvey a blank check to make one of the worst movies ever made and that was the last nail in the coffin for his acting career.