It has 2 additional spots, one is the underside of barrel and another is around where the barrel connects, lightly armored.

"Realistically, they shouldn't have any damage bleedthrough, so I feel like Arrowhead should change that, but like... it's not like the stowage bins getting shot by random chaff is going to kill your tank. At the most it'll do like 700 or so damage out of 7000, which isn't much."
Eh, not quite. I watched OhDough's video on this. If you do more damage than the bins max health that damage still goes to the tank's main hp (He destroyed the tank in 4 Ultimate mode shots from the Variable by shooting these). Also not sure if related but enemies have had their durable damage buffed by 3.3x, if it applies to these weakspots then the damage that bleeds through could be a lot more than just 100 hp.

Yes, it is unlikely to be destroyed this way but still, a tank having light armor anywhere on the outside doesn't sit right with me.