With a tiling WM (like i3), most of the time the whole screen is used. So, currently I have Firefox open full screen. But if I do decide to open another window in this workspace, it'll nicely cut the screen in half and put them side-by-side. So, if you are a mostly-fullscreen person, then the tiling WM workflow might do what you want automatically, more often.

Sometimes it feels sort of like using tmux full screen in a terminal, but some of the panels can be firefox or a PDF reader, haha.

It strongly depends on your workflow. If you generally have a single thing maximized on your primary display then a tiling WM will be a big upgrade. i3 (or the Wayland equivalent: Sway) are a great gateway.

I can't say much about floating WMs, as the above paragraph applies to me. They do exist, Hikari seems to be doing some interesting stuff.

As a NixOS, Magit and i3wm user, I think you should give it a try. I also like to have windows maximized most of the time, but it's nice to have i3 precisely for when I don't want that.

This is the workflow I have in MacOS and I hate it. To each their own. Instead of swiping back and forth I can tile more of what I use on a single monitor. And I can use hot keys to jump to my numbered workspaces.