What components draw the most power in a wireless receiver?
MOSFETs need high current to achieve high transconductance and thus low random noise. Also, for low distortion, low 2nd order and low 3rd order distortion, achieved by designing for high intercept-points 2nd and 3rd, you need high currents. Thus that front end amplifier (LNA) is the hot spot.

However, if you are in a strong-signal location with low interfering tones in nearby channels and low out-of-band blocker energy, the Receiver control logic may measure the BitErrorRate or the residual errors during the initial adaptive-equalization time, and decide the LNA current can be reduced.