Correct me if I'm wrong, but I'm not aware of any coins being made unspendable by the removal of OP_CAT or by BIP 147. This is in stark contrast to the millions of coins owned by potentially hundreds of thousands of people which would be made unspendable by depreciating ECC.
I don't think they have either but theoretically speaking they could have. I agree that it is a bad example but there hasn't been any drastic changes to the protocol for any drastic example.