Something being irrelevant in war between nations doesn't mean that it is irrelevant at all scales. You could make the same argument about a Spanish galleon, and that for historical accuracy it should be stocked with at least a few tons of gunpowder, but I'm still not allowed to stockpile more than 50 pounds of black powder. And that's reasonable, because there's a lot of other uses for large quantities of gunpowder.

Rearming a 70yo tank greatly increases the likelihood for neighborhood disputes to become, um, "explosive".