I see how the website gives that impression, which I assume is an attempt to push non-technical users toward an install method that does not lead to support requests and helps fund the project.

The site also mentions that you can build it from source for free, so it’s not technically claiming that it’s only available from the Play store. If you follow that link, you’ll see that availability on F-Droid is prominently displayed on the README.

Huh? Which messenger requires a Google account? I’ve been using both Element and Conversations on Google-free Android devices with accounts not connected to Google for years.

If a distribution didn’t come with any default software, it would be unusable out of the box by the average user. If you want that, choose something like Arch or Gentoo or LFS.

The point of FOSS is freedom and choice. You can choose a distribution that aligns with your needs, and once it’s running, you can e.g. replace Firefox with Chrome or use Nautilus instead of Thunar. Try uninstalling IE/Edge or Explorer on Windows for a direct comparison.

some areas have active nextdoor.com marketplaces, but you have to prove your residence by receiving a code in the mail.

Brew for native commandline apps, Distrobox for software that runs on other distros. Boxbuddy (GUI) is an easy tool to create and manage distroboxes, and the default terminal app, ptyxis, allows you to switch distros easily from the top-left dropdown.

And more options in the Bazzite docs https://docs.bazzite.gg/Installing_and_Managing_Software/