I’m vert far from convinced wide dispersion is a good thing, and I suspect it is a total disaster with large multi-driver speakers and could well be the reason I don’t get on with so many of them. FWIW almost all the large speakers I like are either horns or panels.
The more a speaker beams treble and mid at the listener the more time delay there is between that direct sound reaching the ear and the splash, flutter or other room effects as the rear wall largely becomes the first reflection point. The ear is vastly better at interpreting and filtering out post-delay than pre-delay, our brains are just wired to do this. Now contrast this with a wide directivity speaker, you are now basically bouncing treble off the side walls, floor, ceiling etc and the delay between direct and reflected sound becomes far shorter, more blurred, and harder to pick apart. This is even more so with tall speakers with multiple drivers spaced out on a baffle which results in comb/time/phase differences between reflections, e.g. the distance of a mid and tweeter floor or ceiling reflection is now different, which becomes an issue (comb filtering etc). The systems that almost always sound the worst to me tend to have fairly tall multi-driver speakers in rooms with inadequate damping (e.g. no carpet, minimal furnishings) and listened to at quite a distance so the room really takes a hold. I struggle with this sort of sound as it sounds so unnatural to me and it tends to give me a headache fairly fast!
I also believe mini-monitors play by very different rules, closer to that of narrow-directivity as one tends to listen up-close in the near-field, so the direct sound arrives well ahead of any destructive room reflection. The thing good horns, panels and mini-monitors all have in common is an almost headphone like clarity, which I’m sure is down to the strength of direct sound/lack of destructive reflection.
PS Credit to Paul Klipsch for helping the penny to drop on some of the directivity/time-delay stuff. I’m convinced he hit the nail on the head half a century or more ago, though he was obviously arguing from a corner-horn perspective.