And will terrain shadowing be modeled along with this? Seems so but still...?

Yeah!

During 1959, the locations of the SA-75/SA-75M Dvina (SA-2A/B) units in Hungary were selected against medium-high altitude targets.

Twenty years later, during the planned re-organization / re-equipping to S-75M/S-125M/S-200VE/S-300PMU (SA-2E/SA-3B/SA-5B/SA-10B) the locations were re-selected to be able to fight against low altitude targets...
... just the money went out (at the end of the Cold War), and some units were stayed in legacy positions (bottom of valleys), so they had short visibility range for low targets.