Placement of components on PCB
Vias, if properly designed, have can have little or no significant impact on RF performance.  We build RF modules all the time, using various substrates, stackups, and layer counts, operating at frequencies into the 40 GHz range.
But, every type of via is modeled with a field solver like HFSS or CST Microwave, and the results of that model added to a chain model (like ADS) of the entire RF path to ensure that the entire path meets performance requirements.
Also, there is always a ring of ground vias around the signal via, whose placement and spacing is adjusted to make sure the impedance of the signal via is correct.