It comes down to 1. content (especially 4-man) get easier every expansion 2. there is less and less to heal even in harder content and 3. the dps healer dps rotation is mind-numbing boring since you basically press the same 2 buttons. I would be ok with the two buttons if we need to use our healing kit more often. Even at the hardest content the difficult comes mostly from remembering what to do when and where to move, meaning you need to remember where to stand etc. rather than improving your skill usage. There isn't even healing needed when people are new and mess up since most of the failed mechanics these days mean insta-death.

In general, everything (content and classes) in FFXIV feels more and more like it was designed with whiteboards and spreadsheets. And while there is no way around that, it never should FEEL like it was designed that way. It's probably because the same design people (for classes and content) do the same stuff for too long.