First of all, thanks but I‘m familiar with sysadmin stuff and a (web) browser is not the same as a repo.
I‘m talking about something like the appstore that you now have on most OSs. It needs to be open so no single corporation can control it. And it needs to be the same on all OSs for this browser issue (although one could argue it should be the same for everything).
And no, I‘m not talking about things that are just not available for windows/linux/macos but aside from that, the ui, sorting should be similar.
That way you make it impossible for MS to push edge, for linux to push firefox and for google to push chrome.
You visit the appstore and install your browser, then you can go online.