No, #149 and #181 were responses, harsh, to be sure, to a pretty inflammatory statement. Those responses are no more off-topic than the statement to which they responded.
r9etb made a slanderous post at #227, and has conceded, at the very least, that it's not true of eveyone to whom it applies. Yet he's declined to retract it, and as can be seen by his post at #292, feels the conversation is over.
Frankly, does it really matter what's "on-topic," when a slander has been posted? Don't those who've been slandered deserve the opportunity to confront the poster who did so?
Posting a slander and then claiming that rebuttals are "off-topic" strikes me as an example of hit-and-run debating.