I removed my center channel
And dialog finally sounds like it's coming from my TV instead of underneath it. Almost everything I watch is in stereo anyway so it was barely being used and when it was it was honestly kinda distracting. The advice I always see online is that you need one but I think that only applies if your "home theater" is actually the size of a theater. My room is pretty small so it's better without. There aren't that many sitting positions. The only disadvantage that I've seen is I can no longer increase the center channel volume separately in my receiver settings but I haven't ran into any problems understanding dialog.
Having discreet speakers on either side of my TV did make a noticeable improvement over using a soundbar. Getting actual stereo separation is nice and does make a difference despite my small room size.