There is a third option besides replacing your window manager with EXWM or a simpler tiling window manager: to manage desktop windows from within Emacs using your existing X11 window manager or Wayland compositor. This means - you can position and resize all desktop windows, - you can switch between Emacs and desktop windows by moving to the left, right, up, down window and - you can switch back and forth between a named desktop app like Firefox, okular etc. and Emacs.

You need to install just the Emacs package Emacs Desktop Window Manager (dwin) https://github.com/lsth/dwin, for example from MELPA. Currently it works with X11 window managers as well as with KDE/KWin on Wayland or X11 (using xdotool and kdotool, resp.). I am using it all day myself on KDE/KWin Wayland in my standard setup and there it works fine.

(I am the author.)