All tank that carry ammo in the hull are prone to impressive cooking off in the hull if hit at the sweet spot.
99 have a carousel so if you have ammo cooking off, it will be like other MBT with ammo in the hull like Russian, English, German, Israeli and France MBT in service.
A penetration into the bottom of the hull is nearly universally fatal, ammo stored there or not. T-14 and supposedly the undesignated new PLA tank have armored capsules that would in theory protect the crew from a catastrophic lower hit, but it doesn't stop the tank itself from being destroyed.
M1 have the advantage to store ammo outside the crew compartment but at the cost of having it's ammo way more exposed with a turret hit. It would not explode in the tank hull if the blast door are close ( When not recharging the gun) . So the crew is safer if no ammo are carried in the hull. M1 had possibility to carry ammo in the hull too...i don't think that storage is used anymore.
It's very dubious if this is actually an advantage. In the battlefield, a M1 effectively only has whatever thin armor shields the blowout panels in the turret, which will be the most exposed part of the tank. The crew can often survive a M1 being mission killed from ammo cook off, but then you have a likely wounded crew stranded as dismounted infantry in a modern battlefield environment where their survival chances range from low to very low.
The Chinese/German/Russian/Israeli 3rd generation tanks will have the crew instantly killed if an ammo cook off happens, but it's much more difficult to hit the low part of the hull (which is also more armored), and an equivalent hit to a M1 will also kill the crew, although not in an equally spectacular fashion.
I think there's a good reason why almost every major tank building nation uses ammo stored in the hull bottom, and why both 4th generation tank designs use carousel (with added improvement by armored capsule, which saves the crew but still leaves the tank destroyed).
M1s were designed firstly in an era where they just needed to match the T72 in frontal protection while having a defender's advantage, and then secondly every upgrade afterwards focused on partisan suppression in the middle east.
Having the ammo cook off and leaving the crew stranded is fine if youre not fighting regular military adversaries. It's probably even beneficial through a mineshaft canary effect, where if a M1 gets crossfired by RPGs and gets mission killed, it reveals that the danger in the area is high, while the crew can still run out of there, because they're not in a modern battlefield environment.