The extension disabled itself due to expiry in this case, but it sounds like OP is upset that Mozilla can remotely disable extensions used by Tor users at will with a kill switch (which they didn't use here, but surely exists to combat malicious extensions).

Some other people are also upset that the Normandy system has the capability of pushing extensions that it does and that it is apparently on by default.

These both seem like reasonable concerns that are unrelated to the expiry but highlighted by it.