Many physical games (TTRPGs and similar) will have multiple files available for download after purchase. Sometimes, the number of those files is quite big, with, say, a core book, a supplement, a set of basic character sheets, a set of expansion character sheets - and maybe 3 versions of each of those in different formats, or different layouts for different kinds of printing etc.

I honestly don't understand why this hasn't been added yet with this website existing for how long it has, but could a "download all files" function be added soon, please?

(moved to the right category)

I understand where you are coming from. I do think you have a valid point. However I made a TTRPG and everything is within one file. There are files within that file. I understand this may not be practical for every game, but this sounds more like a problem on the side of the publishers than itch. A download all button is still a fine idea.

this sounds more like a problem on the side of the publishers than itch

This.

No one forces a developer to split the project into 17 and a half files. If they are small, why not offer a zip, plus the individual files.

(From a technical aspect, a download all button does not work. It would only be possible to be a workaround, where the server just packs everything into one archive, but the server does not know about redundancy. This is the work the publishers should do. If they split it into many tiny files, it is their fault.)