dps died...something a healer would prevent...Unfortunately, we are not able to edit our job kits with talents or skills, so we all share the same abilities. You have the same buttons wether you play as a healer in savage or a healer in dungeon roulettes, so devs remove or add abilities to everybody irregardless of their personal tastes or level of experience.
So in a way, it DOES matter how other people play this game. Veterans will see the kits adapted to less skilled players. New healers will see the kits adapted to higher level situations. This often leaves the kits in the lowest common denominator point of design that nobody likes.
Also consider how having a competent party impacts healer gameplay. Competent party dodges all aoes, does mechanics correctly? You no longer have to press your healer buttons. (Not that the amount of unavoidable healing justifies our healing kits either)
Please watch the video. They commit several mistakes, don't play optimally, two of the dps die twice to avoidable mechanics and the party get several stacks of vuln. They don't wipe once. Their jobs have enough self sustain to carry them through the avoidable damage and deaths they take. Maybe the players are experienced, by they are hardly playing at a super high level in that run.
Healer forum also likes this. They don't like their "pew pew pew" being this repetitive though. That's a big point of their complaints. That's why they ask for more "Interesting" filler time buttons.