At least some such cameras were limited to less than 30 minutes, because EU tariffs classified something that could record for more than 30 minutes as a video camera, which had a higher import duty. Source: https://www.borrowlenses.com/blog/video-recording-limits-in-...
Having the camera overheat seems like a clumsy way to do it, though. The time limit would depend on ambient temperature and manufacturing variance in the heat sink.