Doom Speed Demo Archive
https://dsdarchive.com/

Wad: 	   32HNPAIN.wad
Map:       02
Skill:     4
Category:  UV Speed
Exe:       dsda-doom 0.28.3 -complevel 4
Time:      0:29.49
Author:    ELMLE

Comments: This run really shows how low my demo standards were back in the day.
I'm not saying this was completely effortless, it took about half an hour. But surely I couldn't have spent more than 5 minutes on my old run.
I did not watch NiiroKitsunes run because I don't have Eternity installed, but I imagine it went something like this.