Totally!
By thumbnails I would have guessed moded Q2 engine (idTech2, so kinda HL1)

Then again Q1 & Q2 have been rereleased in the recent years (with Doom 3 like lighting & modern Doom-like extra campaigns … I’m just playing these extra maps now bcs I’m less weirded out by what they did or maybe bcs I’ve forgotten about it for a few years).

I’m still glad Quake 1 got so many amazing mods throughout the years (eg of HL1 I only remember They Hunger for some reason).