Huh I didn't know about that. Seems like it uses 8 symbols per bit to increase the range (but I would very seriously doubt you ever get close to 1km except in super ideal "both in a field in the middle of nowhere" scenarios that never actually happen.
Apparently it's an optional part of Bluetooth 5, so not necessarily supported. However I just checked my phone (Pixel 8) and it is supported. You can check in the nRF Connect app.
Regular Bluetooth already has 100 m of range, at least for class 1 devices like most Apple devices. (Many older/non-Apple devices are class 2, which only does roughly 10 m. Very noticeable difference in an office environment using headphones.)
Apparently it's an optional part of Bluetooth 5, so not necessarily supported. However I just checked my phone (Pixel 8) and it is supported. You can check in the nRF Connect app.