I don't think the issues with Concord had a single thing to do with the performance. That was basically the single way the game was fine.

I didn't play Concord, but from my experience of the first 2 or 3 hours is that starts as mostly a movie, you are just watching what is happening in the cutscene, you gotta pay attention cause it moves pretty fast through the story, occasionally killing, racing, minigame in-between the cutscenes.

You eventually get access to build mode that lets you build anything in the world, they have logic nodes for doing gameplay scripting and alot of assets to use, though I only played it with for a few minutes, it takes awhile to get to it in the story I think.

it looks like there's plans for a sort of UGC shared multiplayer type deal, but it's listed as single player so idk