The actual answer is below, but I'm constantly surprised about Lutris being proposed to GoG as opposed to Heroic.
I mean, Lutris is more flexible and you can build more stuff into it, but it's extremely fiddly and not as well supported. As long as you only care about GoG or Epic, Heroic is just hands-off and Steam-like. I actually prefer it to Galaxy on Windows.

What the hell just happened there? That was some weird breakdown.
I mean, I guess you didn't catch the post of the person explaining why Diablo doesn't work properly (Fedi threading issues, presumably?) but maaaaaan, that's some off the rails unprompted weirdness.