Okay, turns out it definitely is a bug then. According to this post:viewtopic.php?f=5&t=19818#p172363
(confirmed by many others) it seems that while fixing the attack to actually do damage (apparently it didn't before 1.15), they also went to reduce the damage from 90% to 50%, and instead accidently increased it to 150%. So it should do about 1/3 (or less, since resistances are a flat absorb amount) of what it does now, which puts it back in line with most of the damage in the game, at least in my experience.
I grabbed the mod he mentioned and edited the changes accordingly... i was going to just leave it, and stack stupid amounts of resistance along with the stupid amounts of armor i had going... but if it was definitely an accident to increase the damage, then i suppose i might as well just fix it, right?! (I was trying to avoid mods if i could)
I will still use the death as a chance to re-do my character anyway though, heh.