5G only has higher node density if you’re using mmWave, which is only happening in ultra dense places today, and mostly indoor/arena use - it isn’t very widely deployed.
5G might get you to within 50ft instead of 100ft, but it’s not getting you to 3ft of accuracy without mmWave, and that’s mostly because mmWave barely travels at all. You can’t be more than a couple hundred feet from the antenna and need unobstructed line of sight to it.
Yeah, when they implant it in your brain, the GPS signal knows which nostril you're breathing out of more. That's why I only use ancient WAP on my 1.7" screen. If it takes me 2 minutes to load a static webpage, my fbi agent will go insane and stop trying.