"Move times are now stored and displayed with a precision of one tenth of a second. The precision even goes up to one hundredth of a second, for positions where the player had less than 10 seconds left on their clock."
Interesting. Thanks for the correction and link. I'll note though the .pgn downloads still only show 1 second precision, as do the game PGNs in lichess's "open database" archive.
According to this blog post, this doesn't appear to be the case since at least 2017:
https://lichess.org/@/lichess/blog/a-better-game-clock-histo...
"Move times are now stored and displayed with a precision of one tenth of a second. The precision even goes up to one hundredth of a second, for positions where the player had less than 10 seconds left on their clock."