So yes, it's FAR less situational than "slows movement and changes vision form 360to a cone" the fact you think it isn't screams bias.
I wasnt interested in turning it into the SUs focus vison. if it wasnt possible to just make the scope work while the vehicle rotated, I wanted to model a togglable ability similar to the SU's ability. So it would not change its enhanced vision. The ability would severely reduce the speed of the vehicle while activated instead. If a doctrinal upgrade is not helpful for the majority of what it applies to, eyou should make it so that it is, and adjust the price accordingly. Hell it could even be a trade off with the pintle mg like the OKW's Panzer commander ability.