Not true, when it's backwards the turrests rear armour goes in the same direction as the shell... like a plan on a conveyor belt... so it's effectively thicker.
There is zero reason to hit the turret !
First, Understand what happens if an antitank shell hits the engine compartment IRL during ww2 :
It enters through the very light back armor, not angled, that is 20-40 mm thick, (front equivalent might be 100mm plus) and hit the engine and or fuel tanks , with very hot fragments rupturing the electrical lines and and other important stuff- causing fires, and you have to evacuate the tank pronto (as most tanks used only handheld fire extinguisher).
If the shell (like pretty much all axis ammunition used ) have explosive content, you will have a recepie for a very quick disaster.
Best way to protect a tank is by angle the front of the tank against the threat, and zigzag your way to target area at speed.
I served in tank on an off for 13 years, as a tank officer - as a tank platoon leader if war should occur.
I crewed the IKV 91, S-tank, and to a lesser extent - the Centurion 101-102.
Use the max gun depression of a tank, it will make you a smaller target and harder to spot, specially if you can camouflage it.
I never played tanks when I played AH, but I have more than a clue about RL.