On a serious note, I imagine that Erel has set some sort of sane (but high) value for max chars in variable names. It's not really related to Java only, it's also the cross-platform aspect. Imagine a developer using B4A setting variable names that are 1000 chars all over their code. And once they start to move it to B4i, they hit a brick wall because ObjC only allow 32. (I have no idea what the limit is in ObjC, I'm just trying to illustrate a challenge.)
The same reasoning could be applied to what chars are allowed, which probably differ in Java, ObjC and whatever comes after that. In Javascript this is allowed:
But I agree, this discussion seems largely academic. It's not like it's possible to test, or anything.