I've been having the same problem with my Xbox one, none of my Xbox one or Xbox S/X wireless controllers will connect or stay connected to the console from more then a foot or so away, I've been solving this issue by keeping my controllers connected via a charger cord.
This has been a issue with my console for a while now. And recently I took the console apart to clean and replacement of the thermal paste (recommend for consoles around 10+ years old) and the issue has since only gotten worse. Now sometimes controllers just won't connect at all, even when they are sitting right next to the console.
now I've taken the console apart and made sure the connections between the motherboard, Wi-Fi card/chip and the RF receiver are connected, I've also ruled out the possibility of it just being to close to the router.
I'm starting to think I may have to replace either the Wi-Fi card/chip or the RF receiver or possibly both.
If this is the case, would it be possible to use the Wi-Fi card/chip and RF receiver from another Xbox One original or is there something that would prevent this?