Threat Interactive is a grifter.
The guy started YT posing as a game dev who really-really wants to make a game, but Unreal is apparently holding him back. So instead of working around the limitations (you know, like any other gamedev would), he started a pledge for a budget to pay a team of rendering engineers to fork Unreal Engine. In the meantime, instead of developing things that don’t depend on rendering (like a reasonable dev would), he starts making ragebait (non-AI) slop on Youtube, feeding off gamers being angry about games not performing well.
No matter if some points are valid, the guy is ultimately destructive and people should get their Unreal optimization tricks somewhere else. He is basically clueless about actually developing games and seems to have no intention to change that.
How exactly is DXR or vulkan RT not vendor agnostic?