It seems like YouTube is auto-generating timestamps for some podcasts. I only noticed it for some of the shorter episodes, like Hands-On Tech and Hands-On Mac.
Edit: I tried asking ChatGPT to generate timestamps using a transcript. It did pick up on some of the topics, but the times were always incorrect and incomplete, so it’s not really usable. At least with the keywords I tried (“Create timestamps of topic changes using the following transcript: pasted entire transcript”)