Because design and game balancing aren’t as much connected as people think.
It’s really easy to have a really fun game that isn’t really well balanced. I sure many people here can suggest some.
Day 1 DH is easy both well designed and overpowered.
With that said. I not against balancing the game. I against people trying to solve issues they have with design with balance decisions.
This is the only game were i see people suggest that devs should hide what they consider as mistakes by nerfing they so much that no one gonna want to play with it for example.