Brolly is a psychopath and enjoys torturing others. He's screwing with them like Alucard screws with other vampires and ghouls shooting him up.
Pretty weak excuse to try justifying why someone who supposedly destroys galaxies is only crippling his foes with blows instead of easily killing them.
lso believe the Daizenshuu and Kanzenshuu confirmed Cell was a system-buster so all the Z-fighters were relatively close to that level at the time in Movie 8 and then Goku was above that in Movie 10.
Proof, especially considering you and I seemed to be on the same page a while back that Cell and other DBZ characters can only bust planets?
Besides, having planet-busting energy =/= planet-busting fists. DBZ never worked like that.
The planet busting in DBZ was always via ki attacks anyway. No one in the franchise has demonstrated the ability to destroy planets through raw strength, even if one were to factor in non-canon source material like the TV anime and movies.