Is "crazy" ableist language?

I was just reading some comments on a blog about #GamerGate and they got into an argument over using the term "crazy" to describe the gaters because it's ableist and offensive to people with mental illnesses.

As a person with a mental illness, I was not offended. Hell, I didn't even notice it. At first I was confused over who was abling who and with what word. There are levels of crazy and these GamerGate morons are batshit crazy. I'm crazy--but I'm a normal can't-control-my-mental illness crazy. I've embraced my craziness and the word. I was in the "crazy house" and I take "crazy pills."

I didn't realize people got offended when calling instable people, "crazy." Everyone I know (in real life) would not equate the "crazy" of people like gaters and the "crazy" of people with actual mental illnesses.

Maybe I'm behind the times or not up to date in PC terminology.