Healers need other ways to contribute to party DPS instead of boring filler spells.

[Ekimmak]

The issue is this game simply allows for so much downtime, if you aren't actively DPSing, you will be functionally useless for a majority of any fight, including Ultimate. It isn't simple DPS should just DPS more, damage is damage. Why ask your DPS and tanks to contribute as much as possible; keeping their GCD rolling to the tune of 95-99% efficiency while yours isn't even half that? You're expecting the group to do more now because you aren't willing to contribute. While you may prefer healing, FFXIV isn't the game for you then—no matter what the devs argue. They can prattle on about not expecting healers to DPS, but when upwards of 80% of your casts will be a DPS spell, the community will expect you use them.

While I agree with everything you said, I can understand why the healer DPS spells aren't complex.

It's because they need to be something that can be dropped instantly to focus on healing.