I think the parent commenter is perhaps a little over-selling the LG rooting. It is definitely root, you can write whatever you want on the filesystem (at your peril), and theoretically do whatever you want, but the homebrew exploit launches a bit later in the boot chain than you'd want (so blocking update nags isn't quite reliable), and a lot of the inner system things are proprietary and require reverse engineering to extend.

It's the same system software, just with root capacity.

That being said, there's still a bunch of nice homebrew:

- Video screensavers ala Apple TV

- DVD logo screensaver

- Adfree (and sponsorblock-integrated and optional shorts-disabling) Youtube

- Remote button remapping (Netflix button now opens Plex for me)

- Hyperion (ambilight service that controls an LED strip behind the TV)

- A nice nvidia shield emulator for game streaming from my PC with low latency

- VNC server (rarely useful, but invaluable when it is)

Sponsorblock and remote remapping are killer features for me, and the rest is just really pleasant to have.

I used my rooted TV to root my PS4. I'm not even joking.

https://youtu.be/NzBBfGnAWM0