It seems to rely on Homebrew to set up all the other pieces which is, on my book, a hard no. The suffering I see in my org with Homebrew's reliance on pyenv (it only provides 3.9 - Big Sur provides 3.8 and all the rest is via pyenv) is enormous. I have moved to MacPorts for most of the stuff I need and it makes the machine a lot more like a straight BSD-based Unix, with the added benefit everything can be removed by an `rm -rf /opt`.
Another problem I see with this guide is that it seems a little dated, especially how it assumes you're going to install Alfred instead of using Spotlight, which keeps getting better and better with each macOS update and is almost feature-full enough to forget about using Alfred.