I used to make graphic art in Paint.net myself, anyone who thinks photoshop has anything special is objectively wrong (we're going to ignore generative AI tools)

The benefit of photoshop is that's its more refined in what it does, not that it does anything extra that these foss tools can't do.

The tooling has years of iteration by paid developers and there are a shitload of high quality presets and brushes and, again, refined use case specific stuff, but yeah GIMP is just as viable as a software to achieve most of what photoshop users online who shit talk it can do. The only people whose opinion even matters is professionals who require photoshop to make money for their bills. Everyone else is just blowing smoke out their ass about it because they think having a better tool automatically makes them better.