This is an old quirk but it’s something that I think about often.
The impulse when you see a scary enemy, like a mutie or rager, and you’re holding an axe is “Ok, I’ma need a big whack for this one”. Doubly so if you’re a zealot who’s about to hit ult. You want to charge forward, holding your steel high, and bring it down on a heretic’s head. It’s counter-intuitive that the damage values are swapped between heavies and lights. The heavies of any weapon should (almost) always do more damage! Why on earth would we sit through the slower animation otherwise!
What’s even more annoying is that this issue WAS SOLVED at one point but Fatshark backpedaled on the swap due to public outcry. I think the outcry at the time wasn’t really about the axes, more so the community was furious at the state of the game and couldn’t stomach a “nerf” to one of the few actually good weapons. It could also be due to how painful literally any balance changes are since locks exist (#breakthelocks). So Fatshark reversed the decision to placate the player base.
I do think now that the waters have settled a bit and that this problem should now be fixed. It would feel intuitive and give more reason to use heavy attacks. That’s nice in a game where most melee combat is mindless spam clicking and dodge dancing. Also it’d give Ogryn’s Intimidating Presence more value! It’s not often remembered but that is a coherency-wide aura 
