Why the rush to 30mm and even bigger when the 25mm APFSDS has shown to be effective against the side armor of tanks?

 

Just a quick question.

Why the rush to the 30mm and bigger when the 25mm has shown to be effective against the side armor of tanks, capable of destroying tank optics and other bits from the front and totally capable of handling IFVs operated by threat forces?

You have more stowed kills with the 25mm.  If you have good gunnery coupled with modern optics then you can basically sniper the hell out of enemy infantry at distance and close up too with the added benefit of having a metric shit ton in storage at the moment?

Broadly speaking is this a move that makes sense or is it just the latest trend that everyone is following.

We're already moving to "light" tanks so let them or MBTs do tank shit.  Let our IFVs specialize on their primary mission and leave the shock and awe to the big guns without bastardizing the class.