Why do Respawn hate Octane?

I fear that if they remove the stim health penalty, they're gonna have to move that penalty elsewhere to balance it. The most obvious choice would be the cooldown; no health penalty, but CD increase to 10 seconds or something. That would ruin Octane.

Cooldown is merely a balancing concept. There's no reason Pathfinder can use his grapple only every 35secs besides balance.

What makes Octane interesting (for me) is that the concept of cooldown is taken out of the equation and placed into the player's hands. Maybe you want to stim once, maybe 4 times in a row, the drawback is obvious; you lose health. There's a clear distinction between the drawbacks and advantages of each choice. It also adds a risk-reward factor to consider, maybe you'll need the health you wasted to use stim sooner that later.

The passive makes that health investment into a more short term commitment, and even has its uses besides counteracting the harmful effects of the stim, like negating some damage if you find yourself into the ring, should you get out of it in time. All in all, it's a nice equilibrium.

"Overclocking" is always an option to you should you choose it, and simply no other Legend offers that. That's what I'm afraid is going to change should he get a rework.