Annoying, to say the least. I want to install Fallout4 and whatever option I take: GOG always creates a folder "Fallout4 GOTY"
Let me decide which name the final folder should have, I would simply like it to be Fallout4.

You can only change where the GOG client should try to place the downloads or the temporary files but not the game itself. So please no references to the cog on the left side because that doesn't work.

Can you name at least one digital store app that allows similar things?

Two workarounds for this...

1. Use the offline installers. Here you can change the folder name by clicking on "Options" and if Galaxy is running, it will recognize the game once the installation is finished.

2. Rename the folder after the installation through Galaxy. Restart Galaxy and re-add the game by right click on the game's cover - "Manage installation" - "Import folder".