Wasn't this the case for a long time? Since they started deduplicating the root partition and making it read-only/ a pain to write to?

Edit:
https://github.com/Universal-Debloater-Alliance/universal-android-debloater-next-generation/wiki/FAQ

Tldr: You couldn't uninstall from /system, only from /data and now you can only disable them. Looking at the wiki also shows that there's not much difference between a data-only uninstalled system app and a data-only disabled app.

I don't think so, but that could be wrong. Per the linked discussion:

Potential harm: [M]ost of the already listed apps are primarily tested for uninstalling rather than disabling

To me, this heavily implies uninstallation was possible before. Can't say I'm technically competent enough to verify this though.

All I can say I just used ADB to remove bloatware from a new TV a few weeks ago.
The last smartphone was in 2025.

I wouldn't put it past TV manufacturers to use older versions of Android.