Of course not doing damage in a dungeon is going to rise some eyebrows when you can easily heal said dungeon with zero gcds even in nowhere near best gear and a tank who doesn't know what Rampart is, while your damage "rotation" boils down to spamming a single AoE spell over and over. However even with that I will just roll my eyes maybe and still not say anything, because who cares - it's just a stupid dungeon.
Given the performances I generally see in dungeons and the silence alongside it, I'm inclined to believe that majority of players share my attitude of "silently judging but not being too bothered". I'm sure some people do indeed "lose their minds" if you say so, but given that I've never encountered it I doubt it's particularly prevalent.
As for savage, I guess you'd be surprised how many healers perfectly get by doing less than half their job's potential rDPS. In PF nobody will complain unless the group keeps hitting enrage and it's obvious that healers are at fault - and even then you will often still see a lot of people jump to defend them as "that's not their job, the DPS should stop blaming healers" - but keep in mind that is while:
1) basic healer dps revolves around casting one damage spell and one DoT whenever there's nothing you need to heal, which is extremely little to ask
2) the current dps checks actually do require healers to output a bit of damage.
The ease and the requirements are why people expect you to do something at least as it's far easier for group's healers to just start dpsing a bit instead of standing around, than for the DPS players to suddenly get better.
It's not about being "happy", but about what is seen as "acceptable", so my personal feeling in regard to somebody's competence is irrelevant.
I don't think you actually understand what meta means if you believe that. It stands for "most effective tactic available" and generally refers to whatever playstyles or group compositions are the most effective. Adding more complexity isn't really a meta-oriented suggestion, especially when I'm coming from the perspective that it's okay for less skilled players to perform worse(aka less effectively). They're not even in the same "category", as meta has more to do with balance than gameplay - ex. how much damage you can deal, not how you go about dealing it. The stance of "it's okay as long as you can clear" is pretty much the opposite of meta.
If anything, being upset over a prospect of doing less damage at your current skill level is more meta-oriented, since it suggests being afraid of losing effectiveness.
Allowing for a bigger skill gap between players while still letting them all clear isn't excluding anyone, from the content at least. It will exclude them from the meta, but majority of players will always be excluded from it by meta's very nature of being defined by peak efficiency.
As for healer's primary role it has always been healing, I don't think anyone is ever disputing that. People just generally expect the healers in FFXIV to also perform their secondary role - which is dps - on top of that, especially now that one can do so with such ease. It has nothing to do with "agenda".