F-Droid does not ship binaries. You submit code to be built by F-Droid. This is its strength and also weakness. IzzyOnDroid just pulls in Github releases, which is pretty cool.
It was just my info that they directly use Github releases. Shipping binary packages next to the codebase is something specific for Github and a few other platforms.
A few other platforms like Forgejo (Codeberg), GitLab, & SourceHut? The first 3 open source/open core Git forges I looked up support this… it is not unique to the Microsoft-owned, proprietary offering.