If you touch those files into existence and chown to root and chmod to 0, it shouldn’t be able to ever overwrite them right?
yeah, should work. Will try readonly on windows too.
Now I can't see it anymore, but shouldn't the model be under chrome://on-device-internals/ -> model-status?
Maybe you can uninstall there too.
I'm on my phone now so I can't check if something has changed, but what you want to protect from change is the directory, not the files. A file can be deleted and created again if the process can write the directory.