I've figured it out.

Xianti is not the type to ban gabe right before April fools day, realizing it could obviously be an april fools joke. He'd probably wait a bit and then see if gabe still wanted to do this. Unless of course gabe had been so convincing in the pm that X-man decided that he truly wanted this.

Banning also seems very unneccessary, as gabe can just not post easily.

I think we aren't going to hear from gabe for awhile though. Even if the original intent was as an April Fools joke, he may very well not post for a month and come back then, making it not a joke at all.