No, he didn't. If he had been using it "against" the BBS, he would have set the post count to 3,000 from day one. He held the power to destroy this board in his hand, and declined to use it. That makes him a "white hat". Indeed, as the BBS software at no point behaved other than as designed, it arguably doesn't even count as an exploit.

I disagree with you. He did cause damage (i.e. annoyance) to the community, and as such, it is an exploit. You might call him a "grey hat" at best, because he didn't try to pull the BBS down (DOS attack).

But anyway, he got a warning when he used the BBS to host a page (even though that was more a proof of concept type thing). Now he did abuse the BBS again, even though he was warned previously. Therefore a ban is certainly OK.
We could remove the ban again after a few days or weeks, but certainly not too early.

cu,
sven