This is fairly concerning. I would agree that post very well could have been made by a bot. However it will be very difficult to moderate (spot) those types of posts. I would be willing to say you probably would not have spotted this if you had not written, or at the very least interacted with, that post. That person may or may not have a large number of accounts, however at the very least, the likely plan may have been to eventually ramp up his operation to many accounts (he could have been testing his bot, AI, etc.,).

One solution to the spambot problem would be to require a captcha to post until you have made x post, have y activity, or some combination of the two. The units of evil system could be incorporated to influence the x and y values.