So this is basically a solution to a problem that is very specific to this TV's formfactor, a problem that the formfactor created in the first place. And maybe a little bit of region-specific architectures.

The TV is on a easel-like stand on four legs. You can't have a traditional media console setup with this TV. You'd like want/need a separate furniture (likely something that is smaller and unassuming in keeping with the aesthetics of the TV) to store any additional devices you might need. If this TV was wired, you would need to run HDMI cable(s) and hide them. Might be easy enough for Americans who have drywall. Easy to cut open the wall, run cables and hide it from plain sight. Might not be the case with other regions that do not use drywall (S. Korea for example).

But by having wireless signals, you are free from cable management which also gives you a bit more freedom in terms of placement of your devices and the box since it gives you up to 30ft.

Obviously, a very very niche problem and a very very niche solution but yeah. I can see why they did this even if it makes little sense for most people. Signature series isn't for most people to begin with.