Quake hasn't enjoyed _as much_ change as Doom, with source-faithful engines like Quakespasm being standard and the likes of Darkplaces being niche. However, the Doom community both embraces faithful ports like prBoom, Crispy, and Chocolate Doom; and carries at its centre the wonderful GZDoom engine.
GZDoom zigs where every other game engine zags. Rather than moving away from BSP into static meshes, and other standard "modern" shifts, GZDoom embraces the fundamentals that make it mod-friendly. It maintains BSP at its core, and while it supports voxels and meshes it remains 2D-focused. What it adds is all the trappings that make it attractive to rapid iteration: good scripting, a toolkit of predefined events, and tools with excellent asset importation and management.
If I imagine where Quake would go, if it were to follow GZDoom's model, I imagine it would lean into Quakeworld's client/server architecture, the QVM, realtime vis, static lighting, and so forth. Particularly the static lighting; which is something I find modern engines tend to treat as a performance feature and not an aesthetic feature.
Both Quake and Doom, but moreso Doom, have unrealistic lighting; with overly sharp and unnatural transitions. When playing modern games everything is softer, the shadows are more natural, the scenes are realistic; but they lose that harsh aesthetic that gave rise to the horror of Doom and Quake. The shadows aren't just dim, they're black, and who knows what they hold.
Anyhow, I digress.
