How to change the date modified of youtube-dl files to date downloaded?

By default youtube-dl sets the modified date of the filesystem to the Last-Modified header sent by Youtube. If you don't want that you can use the ''--no-mtime'' parameter which leaves the modified date unchanged so it is "now".

For more details see https://unix.stackexchange.com/a/387133

you can easily convert the date to the current date, at least in win10, by using the context of the downloaded file, then properties/details, and then scroll down to "media created". Here you can manually change (only) the date...

In python it is also possible, in case you have to do it several times...