I saw this tutorial in the Guides section https://www.speedrun.com/doom_unity/guide/04vox but it's clearly marked as outdated so I wondered if you guys could help me and steer me in the direction of whatever might have supplanted this guide. Thanks :)

Outdated doesnt mean that you cant use it to learn the basics of the run, then after you add new strats by watching the WR of it

It's outdated because at the time of making it, most people including myself ran the game strictly on controller. I haven't got around to making an updated version for PC, but for the most part the tricks in that video are still relevant. Still a good reference video, but there's more that can be added, hence outdated.