I use Lutris myself to run GOG games and have the same experience.

Mind you, sometimes I do have problems and have to tweak things to get them to run (usually switching the runner to wine-ge instead of wine-staging).

It's very rare to be totally unable to run a GOG game in Linux with Lutris.

I would say that my rate of success with Steam is roughly the same.

That said, in Lutris I can run my games sandboxed with networking disabled, which I cannot in Steam (even if I started Steam itself sandboxed with networking disabled, Steam itself needs Internet access).

Maybe Steam is a little more seamless for non-technically adept users (of which there are more and more running Linux nowadays), but at least Lutris (and, I expect, Heroic) are way much more configurable and hence give a lot more possibilities for power users to do things like sandboxing or even to solve problems with running some more obscure or AAA games from a certain DRM-heavy era (for example, there's a game which no matter what I couldn't get to run in Steam, but with a bit of tweaking I could get a pirate copy to run in Wine under Lutris - still now that game is listed in ProtonDB as not running in Linux)