I mean, I get it. But again, it's the same thing. If my main is White Mage, and it gets changed in a way that I don't want, that's bad for me. So if Player A and Player B both play White Mage and both want different things, whether the job changes or not, one of them will be at a loss.
So, given that situation, if you're going to change White Mage in a way that will alienate a certain set of White Mage players, there are two basic ways to do it:
1. Change all the healers so that they all have the feature that alienates this set of players.
2. Change some healers to be the new way, but leave some to be the old way.
With the first option, if you're a player who is alienated by the change, too bad, sucks to be you, this game no longer welcomes your preferences. But at least with the second, even if you aren't getting your first choice, even if you need to change classes to do it, there's a class where you can still have the type of experience you enjoy, the one that fits your needs.
I think the option that caters to multiple preferences is the better choice because it serves the most people as best it can, thus maximizing utility.