Way too early to tell. It was basically just released in a minor content patch with a lot of people on hiatus. I think you'll have to wait until you see the typical massive player return in Dragonflight before you can tell if its had an effect.
M+ and PvP communities will be the ones that benefit most from this change. Hardcore raiding scene is unlikely to change at all or stop being Horde dominated unless they do cross-faction or co-faction guilds in the future.