Destroying the Enterprise D was a mistake.
That ship WAS TNG. It was easily identifiable, beautiful and just was TNG. Replace it with a souped up ugly warship just didn't fit with TNG. Then you rewrite the characters and have Picard out of character just really ruined the movies. It stopped being TNG and the audiences just weren't interested.
Given how popular the series of TNG was it all the movies were a massive failure in my opinion. To many changes.