For example games with player hapu66. Between 20190714-20220604 is missing 22 games on downloaded games. Probably the reason is Chess960. These missing 22 games was Chess960-games. First missing 960-games was played 20191117 and the last was played 20220130.
I'm not sure if there are any regular human chess games missing from the downloaded file?
I did a quick check of the last about thousand games and they seemed to be in the downloaded file. There were some differences in the game dates. In my old game-file, the game date was one day newer than the one I downloaded now. Strange, because not all games had changes in the game date. I'll try to look into this in more detail in the next few days. I have to use several programs and tricks to get comparable data.
... I am still disappointed that chess.com does not allow all games to be downloaded at once on its website, as it used to be. ...
I don't believe an all games option has been available, at least not since I have been a member. It's always been one page of the archive at a time