Let's make it nice and simple, you need to advance across 10km of open terrain to capture a fortified town, are you going to be walking it carrying ATGM's or are you going to have MBT's, IFV's and APC's moving on it? The enemy won't even have to worry about deploying armour, their infantry will pick you off long before you get there.
I think you are making my point.
"The enemy won't even have to worry about deploying armour, their infantry will pick you off long before you get there" whether you are in an IFV/APC or not.
Adding the IFV does not change the outcome.
A well equipped defending force in a "fortified town" will hit you as soon as you enter the "open terrain" 10 km out
From 10 kms they will be hitting you with:
Mortars, Precision Guided and specialised homing Anti-Armour (equivalent of the SMART 155 rounds for artillery).
Drones
Loitering munitions.
Long Range Guided Weapons e.g.Spike ER II (10km range)
From 5km the regular ATGMs will join the attack.
How will being in an IFV prevent this from happening.
Will the 30 mm IFV Cannon supress the enemy mortar teams or other weapons teams from 10km out? Nope
Will the heavy armour of an IFV prevent a top attack mortar or ATGM from killing the vehicle. Nope
Oh you say "I'll add an Active Protection System". Not sure how well it protects you from Mortars or top attack but even it does, the same APS could just be added to a light armoured vehicle to give the same degree of protection. It is not anything intrinsic to the IFV which will protect you in this scenario. You will be just as protected travelling in a Light Armoured Vehicle, say a French VBMR Griffon (armoured against 14.5mm APS) with an APS.
Alright you say, "It is not the IFV, in this scenario which protects the Infantry, it is the other aspects of Combined Arms, like air power, like artillery, like attack helicopters." Exactly, so why is an IFV vital in this scenario again?
And just to get one thing clear, I am not advocating you walk everywhere. You need protection from Mines/IEDs and small arms wherever you are travelling. But the fore mentioned VBMR is an example of a light vehicle that can do that. Just don't think you can use your vehicle to close right in with the enemy.
I suppose what I am saying is that the idea of a vehicle which can carry the Infantry right up to the enemy and then kills them (i.e. an IFV) is borderline not viable Today and will only become less so as anti-armour technologies improve in the future.