I never understood the DS9 vs. Babylon 5 rivalry. They're both great shows and having both is like your favorite band releasing a double album.
I watched DS9 as a teen and Babylon 5 as an adult. Im probably 51-49 in favour of Babylon 5.
I see DS9 as having 3 major issues, with only 1 of them being with the show itself.
1. It came off the back of TNG which I hope isnt controversial to say was peak Trek. Despite being a great show, that dip will always feel disappointing even though it’s inevitable, quality can’t go up or stay stable forever.
2. The fixedness of the station. Again, story was great, but in the context of being a part of Star Trek it makes everything feel smaller and more localized. This is less of a problem when you have a new IP like B5, it allows for more changes to the feel of a show.
3. The plagiarism allegations. I personally think it’s unlikely plagiarism didn’t happen, and while they were definitely unique enough, I find it offputting.
I think if DS9 had either stuck closer to the ship formula or had not mirrored the B5 overall storyline (There were plenty of great DS9 storylines, either isolates to an episode or that could have been disconnected from the gamme quadrant like red squad, you don’t need the overarching story to tell a lot of the small stories in it), then the two would not have been so divisive.