Sure.

Valve’s operating system is read only and, when steam decides to update, any root level file changes will be lost between updates. This is partly good because the system will always be recoverable and update reliably, but comes with the downside that users have to take extra steps to install some base level packages (things like tailscale, syncthing etc. There’s always work arounds, but it’s not a guarantee that these work arounds will continue to work on new updates.)

OSTree is also a read only file system utility that allows packages to be layered, so users can install their own packages. When the operating system updates, these packages are rebased and preserved on the next update so user level changes can be preserved.

There’s more to this than that, but basically steam os is dependent on valve updating packages and generally leave all extensions either hand off or need to work around root filesystem. Ostree/silverblue/bazzite allow user modification by having a slightly more sophisticated updating process.