>Unless you are ideologically inclined, it would be a better use of your resources to just pay for photoshop.

Naw, there's better answers than that:

FOSS: Gimp, Krita; non foss: Affinity photo is a one-time purchase, at least for me. I haven't checked recently to see if that's changed.

>anyone using it professionally

Use what your boss tells you too/pays for -then it's not your problem.