In the post you replied to I stated two specific benefits of dark mode. I don't understand how you got from that post to "gimmick."

- Dark mode saves battery (for OLED displays). The discussion was on "true dark" Vs. grey. Not dark Vs. non-dark modes.

- Dark mode is useful in low light/dark rooms/night usage.

It isn't a gimmick and a lot of people like it. I happen to be one of them. I'd use it even without any battery savings.