If you weren't referring to the performance of plugins when you talked about the "hit in performance", then you are changing the subject from the quality of plugins to overall editor performance. I didn't say anything about that.
That was my point all along. The people that write extensions in this case are also the people "hacking" on the editor itself, and saying they (or web "devs" in general) are not performance conscious is an understatement to say the least.