shmerl: Yep, I think GOG bit off more than they could chew in this case, and got over ambitious, in result stretching their resources thin. Linux support became the victim of that planning. They should have aimed at something like itch.io first, and only when reaching that should have started working on some huge goals like multiplayer and etc. which are magnitude more complex.
I think you nailed it here. Had they aimed at cross platform support right from the beginning as an actual core product goal, and limited the initial features strictly to storefront, game library management and launching and similar simple features, they'd have had a cross platform baseline client first. The more popular modern client features could be developed incrementally after that also cross platform, and that is an approach I'd have like to have seen them taken.
I think they ended up allocating a lot of developer resources to the higher end features a bit too early under the probably correct premise that the mainstream gamer market expects such features, but underestimating how much time it would take to actually develop it all. Furthermore, their first attempt at developing the overlay didn't really pan out, and they ended up redoing it as an injected overlay, which is what all other overlays out there do. It's not clear if that was a necessary development path to get from point A to B, or if they wasted time going in one direction then later realized they needed to change gears and do it a different way. Either way it took over a year to come to fruition.
It's too late now to change things, but we probably can agree that had they kept it 100% cross platform from day 1, and focused on providing the identical baseline client across all 3 platforms, the Linux user base would probably be pretty happy overall with a basic client even if there was lag with getting certain new feature updates that involve platform specific work. That probably would have allowed developers to actually make GOG versions of their games as they wish, even if the high end client features weren't all available yet.
While hindsight is 20/20, it's all past history that can't be changed. Realistically, I think we'll have to wait until Cyberpunk 2077 comes out and GOG & CDP get another massive cash infusion and can ramp up their hiring efforts and have much larger teams that can be working in parallel on things. Right now it doesn't seem like the Galaxy team is large enough to have much parallel work being done simultaneously. With a larger team working on multiple sub-features, it would be more realistic for them to designate a developer or small team to Linux platform specific feature development and issues however.
Unless they share some major revelations with us, I estimate we'll be waiting another 2-3 years or more for a Linux Galaxy client if we ever get one, and I think that people will have reverse engineered enough of Galaxy in the mean time to have a working downloader/installer/launcher by then. There still wont be a Galaxy runtime library for Linux however, so a community driven effort based on reverse engineering wont end up increasing the unit count of Linux game releases on the platform. That'll have to wait until they have a proper client. Like many have said though, a lot of existing games that do have Linux releases elsewhere are likely to never have GOG Linux releases even once GOG does get Galaxy on Linux up to scratch.
:o(