Probably not exactly what you're looking for but i3 could be worth checking out. It's a tiling window manager with a powerful customization/scripting interface and it has a feature to save and restore window layouts. There's also Sway which is similar but based on Wayland though it does not have the save/restore feature.
Granted they might not be as easy to set up as installing PowerToys on Windows if you have specific expectations. (But it's not rocket science either.)
I'm aware of i3 and I think I've tested it out in the past but had some silly nit to pick about it. Thanks for the reminder - I'll give it another try!
Not at all. It's a tiling window manager with workspaces, for all your applications. Terminals, web browser, audio settings, etc.
Personally I run 10 workspaces, named, e.g. 1:Firefox work, 2:vim, 3:tmux+vim, 4:terminals, etc. I even have a workspace designated to "wasting time", tiled reddit, hn, youtube, etc.
Each workspace always have the same apps, tiled in the same way, so I always know where to find what. It's very efficient.
Granted they might not be as easy to set up as installing PowerToys on Windows if you have specific expectations. (But it's not rocket science either.)