I think this is a dated comment, actually. Scifi is increasingly popular, with multiple CoDs using it, the new Prey, Titanfall/Apex, the upcoming (unless it’s delayed again) Cyberpunk, etc.

CoD and BF both went back to WWI/WWII for some releases as well.

And whatever Fortnite and Overwatch’s settings are. Kinda-cartoon kinda sci-fi?

I don’t think there as many generic modern shooters these days.

Doom is kinda sci-fi and kinda killing actual demons from hell ¯\(ツ)/¯