For the first time in my life, I can say that I have something in common with Attikus: difficulty expressing myself.
You’re underestimating it, I’m afraid. Venom was the bulk of her wave clear, and this is a big nerf to Spike overall (by way of Parting Gift), so it’s not true at all that her kit is unchanged.
Her survivability plummets if she attempts to melee, because her melee string is grounded-only (unless she bounces and uses the elbow, which is quick melee levels of DPS). So she won’t be air stalling or bunny hopping, and you know how quickly Mellka goes down when she stops moving. She also opens herself up to CC in a way she ordinarily never would.
Finally, I’ve seen for myself that few Mellka players keep the regular canister and use it well. Much of my own success was owed to the fact that I am a good shot with a canister and I make sure to keep venom on any target in my sight. Many Mellka don’t do this, and these are the ones who won’t quite grasp why this is such a nerf. For those like me, our killing potential just got pulled out from beneath us.
That, and the fact that Refined Canisters is now a shadow of itself.