> Has GitHub introduced some “showcase” feature, ...
Yes, you can pin repos to your profile. But you can also create a profile repo. See https://docs.github.com/en/account-and-profile/setting-up-an...
I wrote a blog post about this and the profile generator I made for myself - https://blog.urth.org/2022/03/28/yet-another-github-profile-...
Historically, public repos were just where you put code that didn’t need to be private, like hobby code and experiments, just as much as showcase work or supported open source projects.
Has the culture changed so much that this way of using GitHub isn’t familiar to you? How do others here see it?