Can use of higher frequency improve level measurement performance?

For example, 20GHz vs 10GHz, 10GHz vs 5GHz level measurement. Can we get more precision somehow when use higher frequency with same signal processing?
Why I ask this, because recently there are some news on RF ICs for level measurement, which use much higher frequency than current mass production. For such industry devices i think size is not concern, so they moved to higher frequency not because size of horn, etc..

Definitely no. Higher the frequency, lower the measurement accuracy, from multiple causes.
And yes, sometimes higher frequencies are chosen because they use very low dimensions for antennas. For example a half-wave dipole for 60 GHz has 2.5mm length.