I feel kinda of sad because currently the itch app doesn't properly install mods. For instance, my games are foss, so is expected that different people make different versions of them. E.g. Moon Cheeser got modded as https://makizo.itch.io/around-the-moon but from the itch app it installs...some weird files (maybe something butler generates for mods to point to the original, dunno) but we can't play the mod by itself.
So would be very nice if the itch app actually allowed mods to be "self contained" providing someway to install them independently.