And that is indeed your role as a healer. However as I said, FFxiv has stepped a bit further and added an extra side-role for the healers capable enough, and it is damage dealing. Said role is mainly optionnal but the community tries to enforce it because.. reasons (mainly because a healer doing nothing for repeated periods of time isn't exactly efficient when the game provides tools to do something when you don't have to heal).
Without going into the debate, I'd just say that if you are indeed finding yourself doing nothing for extended periods of time, you could throw 1 or 2 spells to appease the guys telling you to dps. For them you tried, and for you, well, you weren't doing anything anyway at that moment :)
No need to min-max your healing to throw in maximum dps as a healer out of the latest raids.
And who knows, you might end up liking dealing damage and start doing it on your own (that's what happened for me).
However,
This isn't a good mindset. Healer dps isn't asked to pick the slack, but to further quicken a run. I have never met anyone asking the healer to compensate low dps except in cutting edge content, because people are undergeared there (and Alexander Savage is even more over the top). I did however met people asking healers to dps because they were afk through the run (fairies being a little too good in low level dungeons ^^).
+ what Kaurie said
I can understand that people don't like walls of text. And it was a mess before my edits to try and put some formatting done, plus spoiler boxes because it was super long. If they really think that it was useless spam though, well, opinions. Everyone has one. Not gonna throw a fit at it :)
