In my opinion, even though I don't play anymore, this does seem like a rather unnecessary change. I mean, the terms OU, UU, BL, etc are all jargon that just about every "serious" Pokemon battler knows. Changing it now just seems to be frivolous and just an excuse to give everyone something to do / new to learn. (Granted, learning tier names aren't that hard) but it's kind of dumb. I'm going to make a parallel between CoD and Pokemon right now, but in BlOps, me and my friends all call the Ghost Perk, Cold Blooded still. Not because we are trying to be edgy or anything, but because we have played MW2 for the longest time. People online also still call it Cold Blooded from time to time. (same for Hacker and SitRep) The old names that people are familiar with tend to stick when they are so oftentimes used, as UU, OU, etc were all so commonly used for the past several generations.
tl;dr - change for the sake of change is often a waste of time and effort, unless there is some huge outcry akin to the Garchomp era, I don't think that its worth it to change around the tier names.