I don't think the built-in tiling in Plasma was ever meant to go mucher deeper than what's in Windows. You're still gonna need to use extensions if you want full tiling, I think.
There are two KWin scripts that can be used to add tiling functionality into Plasma 6, which are Kröhnkite and Polonium. Not sure which of the two is better. If you want to use a window manager separate from KWin, I believe i3 still works.
There are two KWin scripts that can be used to add tiling functionality into Plasma 6, which are Kröhnkite and Polonium. Not sure which of the two is better. If you want to use a window manager separate from KWin, I believe i3 still works.