You try to run an amd64 image on an arm architecture host.
Please try arm images instead, or build one yourself. You can take e.g. the Dockerfile of x11docker/lxde and build it on the raspberry.
Alternatively (less performant) you can use QEMU. Compare https://github.com/mviereck/x11docker/wiki/Multiarch-setups-with-QEMU
Thank you!
It works: https://youtu.be/sCwNRhYtuSw
Commands from video
wget https://raw.githubusercontent.com/mviereck/dockerfile-x11docker-lxde/master/Dockerfile
cat Dockerfile
docker build -t lxde .
x11docker --desktop lxde
FTR, using QEMU for running amd64 on RPi4 might have time/date issues: dbhi/qus#6.