I think there are some pretty awesome third party tools. I am incredibly happy with my setup.
BetterTouchTool + Alt Tab + TaskBar is my setup.
All apps used with any frequency mapped to keyboard shortcuts, mostly using right side CMD key. CMD C Chrome, CMD V VS Code, CMD T Terminal, CMD F Figma, CMD S Slack, CMD E Edge, CMD OPT A Activity MTR, CMD OPT CTRL F Firefox and not that many more.
And then for windows, it's left side CMD OPT ENTER maximize, CMD OPT LEFT left screen, etc etc. And then others for quadrants. If I need to multiwindow, it's rarely more than 3 things, and most of the time it's just 2.
Having alt tab mean cmd tab is windows style is huge. Many of these things aren't directly related to window management but I find myself not thinking about it at all, when I used to think about it all the time with Macs.
iOS on iPad has split screen mode now. It's pretty decent. Wouldn't defend it tho.