You could try starting with some cable management and then maybe move on to more cable management.

Seriously, at the very least why arent these cables behind your shelving instead of draping over the front edge? Thats crazy. Then you have a pc in the middle with cables going both ways. Is that a LAN cable coming from the right? Drill a hole and run that through the wall and either run it along your skirting board or get some trunking.

You can even remove the skirting, cut away a small section from the bottom back corner of the skirt to create a channel for the cable.

If i was you i would reorganize all of the devices, run all the cables in the same direction and as shown in another comment run them down the leg of the shelf and then across to the tv. And move the PC to the shelf. (Maybe the side of the shelf)