At least it seems like they are looking into how to support Linux. I don't see how they want to overcome the problem of "supporting all distributions at once" instead of going for the major one like Ubuntu. Even if you do not like Unity nothing prevents from you using a different interface and still run Ubuntu compatible software.
I know, but that was one of the arguments from the GOG guy in the link. Saying that maintaining different packages for all distros is time-consuming and so on.
No, I don't think he meant that. It's rather trivial. He mean bigger discrepancies across distros. Think one of them using X.org while other already jumping to Wayland and etc. Packaging is a trivial thing to solve in comparison.