When I'm in the appropriate space with only those related windows, the exposé gestures are also much more usable than when everything is jumbled together.
If I uses spaces, I know exactly where my editor is, where my browser is, it is one key press away and it is always there. I use aerospace and I divide my spaces using Alt+ the qwerty keys. Q=chrome W=code editor E&R=programs open for what I am working aka Postman or Obsidian and T=MS Teams.
My dock on MacOS is always hidden because I don't need it and now I have more screen realestate.
One example would be if I’m working on a document that draws on others I have written. Put all three in a space and that piece of work is nicely organised.
When I have all my windows in one space I find it messy and stressful and it’s harder to find what I want.
Overall spaces are more compatible with the way I think than command tab.
It can make sense if you're keeping a lot of non-full-size windows on a larger screen and working on separate tasks that are in the same application, meaning cmd-tab won't help.