This is true, of course, but having a community is completely orthogonal to whether software is open or closed source.
But you can very much allow bug reports and feature requests in public while developing proprietary software and you can also very much work on a project alone or with a small group without being open to random patches, contributions or requests and be open source / FLOSS.
The key definitional question is the license, not any of the cultural stuff.
In fact, github is arguably a poor substitute for a community. Look at how communities such as the ones around the linux kernel or cPython communicate. It sure as shit isn't through issues or pull requests. Or rather, perhaps, the limited technical communication that an issue tracker is good for is not a valid large community consensus building mechanism.
> The key definitional question is the license, not any of the cultural stuff.
For direct modification, certainly. For customization, maybe. For ignored issues like the parent to my original comment was bemoaning? Maybe LLMs are good enough that we are almost ready to say "Make me a custom version of Photoshop" and then it doesn't matter.