So, since Xorg requires SSE2, I tried GNOME as it is using Wayland instead. In the debian installer I kept the default selection for the desktop environment (GNOME, which comes with gdm3). Everything works fine. The other DE which comes with Wayland is KDE, but I cannot install it because that requires SSE2 (libqt5webenginecore5, to be specific).
LXDE is using X11 and X11 requires SSE2: xorg->libgl1-mesa-dri->libllvm14->libz3-4 libz3-4 requires SSE2: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1020802
