Not going to X (or any wrappers) but I'm curious what "supported games" means. Because I would expect that it's actually "games that support timeline markers" like how they integrate rich presence. Devs could just use a new header and implement this nifty feature.
On Linux it would be ideal if they could use pipewire to have separate audio streams for the game, a mic input, and all other PC audio. This is what I currently do using obs' replay buffer for clipping.