Energy fighting.
I'm no expert, I'm the guy who tried the 190 a few times and got frustrated and went back to 109s. So read the next paragraph with that in mind. If there's anything I didn't know or didn't take into account, feel free to update me. I would certainly like to fly the 190 better if possible.
There are better energy fighters (109s, Spit8, 14, 16). The 190s have a hard time converting their energy into an angles advantage (and by extension a kill shot) because their corner velocity is so high and turn performance degrades so much with speed. E fighting also takes time, which works against the 190s strengths of speed and high snapshot firepower. Seems smarter to make BnZ pick passes than to sit and energy fight them.