Elgato Game Capture Neo

For "serious streamers", maybe 1080p60fps is fine - just know that with the new generation of consoles, you typically are going to want to capture at native resolution of 4k60fps, and perhaps even in HDR, especially if you're producing edited content for platforms like youtube. Elgato does sell capture cards which do this, and have so for awhile (https://www.elgato.com/us/en/p/game-capture-4k60-pro). Just make sure you know what you're buying.