For other Linux gamers wishing GOG Galaxy had a client for Linux, there’s an open source project that provides most of the critical features, namely easy download install and updating. It’s called Minigalaxy and available for most distros.
It even allows you to install Windows-only games via Wine, and assuming you have DXVK configured for your Wine instance, I’ve found many games play reasonably well out of the box.
To install it on Fedora, simply enter: sudo dnf install minigalaxy
Then launch it, enter your account credentials, and you’re ready to go.
Find it on GitHub here: https://github.com/sharkwouter/minigalaxy