And from what I read the now use actual projectile physics instead of RNG hit calculation. \
Wait WHAT?! They used RNG in a freaking strategy game? WHY?
Whether you have a simple hit%, or a random deviation + complete projectile trace, there's always (pseudo) randomness involved.
Hell, even if the projectile traces were completely deterministic & 100% accurate, there would still be pseudo-random behaviour from floating point imprecision.
If the (far less computationally expensive) hit% calculation sufficiently approximates the modelling of a physics driven projectile simulation, then scalability* is a compelling reason to use the simpler approach.
*either consuming less power, demanding lesser hardware, or allowing larger battles.