No this is fixed by physics. 5ghz waves are about 60mm wavelength.
Your resolution limit is about 30mm as a result.
There are techniques that can reduce that limit when you have multiple signals, though whether they can be combined with this technique isn’t clear.
Wifi 7 includes 6Ghz band but fair enough
Add a nice prior from a photograph, combine multiple measurements and presto you can pick out a person from a crowd with reasonable accuracy. No?
It applies to the sensor size as well. Such as you need a 3m sensor to get 100px per radian, under ideal circumstances, unless I'm mistaken. (I think I'm not)