Anyone who has read the classic 'Street without joy' will recall that on occasion the Viet Minh were confronted with French armour which they immobilised but didn't have weapons capable of penetrating. Nothing daunted,they simply fired rpg after rpg until the crew were roasted inside the tank. I don't know - though doubtless someone like
kebabking can tell us - whether modern armour would prevent such a fate.
Modern armour would
reduce the likelihood of such a fate because reactive armour detonates outwards, so the majority of the heat energy doesn't touch the hull - so you'd have to fire many more projectiles at the vehicle before you got to the metal bit.
The - at least as pressing - question is, while you're standing around firing your apparently endless supply of RPG's at this vehicle, what is the crew doing with the vehicles own armament, and is it likely that the rest of the unit that this unfortunate belongs to is just going to stand around while this unfolds?
If I recall correctly, the 'roasting' thing was a somewhat rare and unplanned for idea that mostly involved petrol bombs, with RPG's etc.. being used to immobilise the vehicle and keep the crew from being able to use/reload it's armaments.
My own, perhaps rather conservative, view is that planning on winning an engagement by cutting off individual vehicles, and then getting close enough to throw petrol bombs at them, while keeping the crew inside with an RPG or two every minute for the several hours it would take to get the hull hot enough to roast the crew, would be a somewhat
novel, perhaps even
courageous plan...
As ever, look at the evidence: western tanks and IFV's have been subject to an endless number of RPG/whatever attacks in the Iraq and Afghan wars over the last 20 years - the number that have either been destroyed by a catastrophic kill, killing the crew, or been disabled for long enough that an enemy force has been able to roast the unpunctured hull has been a tiny proportion - for the second, it's less than one...
Compare that to the number of Russian tanks you've seen brew up while playing the 'can I get the turret to the moon?' game in the last 18 months.
Crew survivability is something western tanks and IFV's are designed and built around. Russian ones? Not so much.