But interesting that with no time pressure, OSS does not miss lots of features of commercial products. Often their are even ahead.
OSS is usually reinventing the wheel free from commercial pressures (Linux, GNU, Apache). Or they are previous commercial products (Firefox, LibreOffice, Kubernetes, Bazel).
The money is in building a browser around the engine because there you can inject tracking and try to make your product unique.
Windows is profitable, but Linux is competing well on servers.
Many OSS projects have professionals working full time on them.
You're comparing household name with household name. Commercial software has a marketing budget, but free software spreads more by word-of-mouth (or association with a big and processional organisation like GNU), so that's an apples-to-oranges comparison. GIMP isn't very good, as free software image editors go: Script-Fu, plugins, or UI familiarity are basically the only reasons to choose it these days.
The only one I can think of is proper material layer painting in Blender, you can get there with addons but haven't found one that's as good. Genuinely the only thing that I miss, and I do this full time.
Krita has a lot that Photoshop doesn't: https://docs.krita.org/en/user_manual/introduction_from_othe... .