Why Was Congo So Hated On Release?

I'll be the first to admit, Congo isn't a great movie. But it's a lot of fun, well acted, good pacing and fun scenes. It seems like a great 90's Popcorn action-adventure movie. I do know that ever sense Congo came out it's been considered one of the worst movies ever. For a long while in the late 2000s to early 2010s, when list articles were more common, Congo would often appear on the lists of worst movies or biggest box office disappointments.

But why? I get it doesn't follow the book at all. The book has more of a darker/horror-adventure tone and the film is more light hearted PG-13 adventure. Is that basically why everyone choose to hate it? I am also going to go on a whim that most of the audience never read the book either and there are many other movie adaptations that don't follow the book closely and are still consider good movies.

Was it basically all the same critics and audiences that also hated on Waterworld which for a long while was also considered a bad movie or the worst movie.

Congo isn't perfect but I always rewatch it every few years and find myself enjoying it every time.