There are many games, mostly ported from older consoles, that are constrained to 30 FPS due to engine limitation and if the FPS unlocks, the engine goes bonkers. But what about frame gen? By basically generating additional frame, we could get 60 FPS without triggering the engine jank, since the way I understand it, the framegen completely bypasses the game rendering pipeline and happens only after the frame is rendered by the game.
remember RTX Remix only works for fixed function graphics, so games like Doom 3 with programmable shaders will not work in RTX Remix
Half-Life 2 was mainly programmable shaders, but it had an option for fixed function graphics for older computers, which is how it works in RTX Remix