I'm really confused - I downloaded Moom because of this comment, but can't find a feature to switch Spaces. Am I missing something?

Moom is not for switching spaces.

You can use the app in in this post for that.

Or if you want the animation, switching is built-in on macos

What you need to do:

1. Create 6 spaces. This is a crucial first step.

2. Go to system settings — keyboard — keyboard shortcuts… — mission control — expand mission control — manually set “switch to desktop 1” to alt-1; rinse-repeat till 6.

3. Go to system settings — desktop and dock — disable “automatically rearrange spaces based on most recent use”