You don't rack up that many Razzie nominations, not to mention winning some of them, without the movie sucking some serious sh#t. Far worse than mediocre. And they racked up those Razzie nominations in the big categories that are usually used to define how "good" a movie is - director, actor/actress, movie, screenplay, etc. Most of the prequels' "success" with other awards came in the technical areas - sound, visuals, music, costumes, etc.
So while I will give you that the sound, music, visuals, costumes were decent (the visuals being the technical aspect, not the aesthetic part of it - like how FFXIV 1.0 had fantastic tehcnical graphics, but absolute sh#t aesthetics), that's not nearly enough to pull all three of those movies out of the cellar. Directing, acting, story, characters, etc - everything that is actually a reasonable judge of a good movie, were total sh#t.
I suppose you could play the soundtrack on your stereo and run the movies on mute, and then, MAYBE, someone could pretend they're even decent. But that's a big stretch just to defend a trio of worthless movies.