Mount the television on the wall

Just put a cable duct in the wall. We did it the same way.

Cable duct and sockets mounted on the top and bottom flush-mounted boxes (not yet visible in the picture)

That doesn't sound very great at all. No devices surely come through the TV. ;) And there are actually more like three HDMI cables instead of one (receiver, system, BR)... There probably isn't such an HDMI network bridge, right?

And there are actually three HDMI cables instead of one (Receiver, system, BR)

Isn't there usually only one cable from the AV receiver to the TV? Everything else should connect there.

There probably isn't such an HDMI network bridge, right?

Although it has nothing to do with network or bridge, searching for HDMI switch on Amazon yields 154 pages of results.

What is not so great about the (aus meiner Sicht elegantesten Lösung) of the cable duct in the plaster? Here you have the greatest flexibility, you see nothing and can pull through many cables.

I ask myself that too ?!