Where will up-gunning of IFV's end?

The above vehicle is a DARDO IFV mounting a 60mm gun.  The vehicles below are other examples of IMI's gun being mounted on APC/IFVs and even its service on Israeli Sherman Tanks at the end of their useful life.

This will be quick and dirty.

The US Army has jumped on the bandwagon of up-gunning and will put a 30mm gun on its Strykers.  The USMC was all about it with the EFV and planned a 30mm cannon for use on that vehicle.  The Brits are taking it to a new place and are going with a 40mm cannon for its Warrior and Scout IFVs.  The French not to be left behind are doing the same with its Scorpion Project...and finally the Russians are about to take it to the house with a potential 57mm gun on its Boomerang IFV.

But we've been here before.  "Back in the day" IMI developed a 60mm hypervelocity gun that performed well but didn't remain in service long.  Which brings me to the question of the day.  Where will up-gunning of IFVs end?  How much gun is enough to handle anti-personnel/light vehicle tasks?

I stand by my belief that 30mm is the sweet spot and anything bigger cuts down on your engagement capability and will cause crews to hunt for bear (tanks) when they should be killing rabbits (IFV/APC/Logistics Vehicles/Infantry).

What do you think?  Have planners gone too far, demanded too much and ignored the practical limitations of heavy medium weight cannon fire on the modern battlefield?