My computer is always on and my desk is fairly close to my living room TV so I just walk over and load things normally. I usually have a few pages and apps open with various things queued up and just drag the window over when needed. It's powerful enough that I can stream to my TV and continue using the computer for other things if needed. Also I have a VPN to watch content from the UK and NZ etc, and some other ways to have whatever content I want on the computer so I find the experience of having it connected to my TV very freeing.

I also have a remote mouse/keyboard app on my phone that connects to my computer so I can control it from anywhere in my apartment.

This works well for me because I live in a small apartment, when I live in a larger place I'll still have the media computer but probably set it up more like a server and set up an ethernet HDMI hub to drive the TVs.

Ironically, I actually have a smart TV loaded with all the streaming apps and whatnot, but I find the user experience quite terrible and only use it as a last resort if for some reason the computer is out of commission.