Hate to say this, but maybe you need a break from the game. I say this not to be snarky, but based on your posts the development team appear to be in a no win situation unless you get what you want. If you are truly this unhappy and you know based on past events things are not going to change the way you want them to, why further frustrate yourself? There is no conspiracy against healers, but it is quite possible that the direction they wish to take the healers is not a direction you are ok with going. Nothing wrong with that. But when all evidence shows the game growing and you are posting how the devs have a lack of knowledge etc and ffxiv is on it’s way to failure pretty sure based on my experience with gaming it might be time for a change of pace.
I mean can you list reasons that make you happy with the game?
Maybe the new direction of the healers means time for a new class? I say this as someone that had his favorite class changed from what he loved to not fun at the beginning of Stormblood. There could happy for you elsewhere in ffxiv or another game since their development style and opinions are not going to change. They want play experience before feedback. Just something to think about. Again I was not trying to be rude or snarky just thought provoking.