If I stay at a hotel with such a lock how can I tell it's affected? If the hotel hasn't patched it can I patch my rooms door myself without causing issues to the hotel?
The only question is whether they do some hacker shit, or whether they just go to reception and say "My keycard isn't working, I'm in room 123" and reception gives them a new keycard for room 123, with no ID check and no questions asked.
Luckily thieves are relatively rare and 97% of hotel rooms just contain a suitcase of second-hand clothes.
In my experience, keycards fail so often that the hotel workers don't bat an eyelid when you say your card has failed, they just make you a new one.
While I'm sure some hotels (maybe more upscale ones?) do verification, it is far from universal in the USA.