Quick answer: 4A Games' free Metro Redux Next-Gen Update adds unlocked frame rates, DLSS, FSR and 4A TSR, SSGI, 4K textures and a power-optimized mode for Xbox Ally. VideoCardz reports Metro 2033 Redux also quietly got DLSS 5.
The Metro Redux Next-Gen Update is live for Metro 2033 Redux and Metro Last Light Redux on PC. 4A Games had already announced it as a free update for all owners of both games, and the patch notes went up on Steam on October 22.
On PC (Steam, Epic and GOG), the update brings an unbound frame rate depending on your hardware, support for 4A TSR, DLSS and FSR, screen space global illumination, more geometry and texture detail, 4K textures (which need a 4K monitor), improved PBR materials, spatial audio, DualSense adaptive triggers and Xbox controller impulse triggers. The list also includes a power-optimized mode for the Xbox Ally and Xbox Ally X and the Microsoft Store version, plus a long list of community-reported fixes for crashes, saves, controls and display settings.
There's also a surprise the patch notes don't mention. VideoCardz reports that Metro 2033 Redux got native NVIDIA DLSS 5 Neural Rendering support with this update, making it the second official DLSS 5 game after NBA 2K27. Players found a DLSS-NR option in the graphics settings, and VideoCardz says Last Light Redux reportedly supports it too. It works on GeForce RTX 50 Series GPUs and RTX Spark systems, and early player reports point to a big performance cost. VideoCardz also says the console and Windows Store versions of the update are scheduled for October 29.
If your PC doesn't meet the new specs, 4A Games has legacy branches on Steam and GOG (metro_2033_redux_legacy and metro_last_light_redux_legacy) to roll back. Microsoft Store players are warned that saves won't carry over to the upgraded version.