I’m not sure how the person you responded to did it, but LTT has a whole video series on doing just that from what I remember.

I've done this a few ways:

Optical thunderbolt to thunderbolt dock.. so the dock would be next to your tv and you plugin to the dock with whatever. This works amazingly well.

Game streaming over Ethernet - moonlight/sunshine do a great job, on a high quality network it's not noticable. Only downside is they don't forward microphone, so you end up doing some gymnastics to get microphone input.

I run a USB to Ethernet adapter from my PC to living room TV along with a optical HDMI cable, I even have a second HDMI for when I want to run a second portable monitor on the couch arm rest for notes and stuff