This is evolution in action. An ecosystem is generating with different things populating it. Is there a better method than captcha out there? For instance, hide things in html comments that only bots would see and if they are reacted to then flag that as a bot account and silently hide their comments (so that another account isn't created)? Do this randomly so that it is hard to find but bot code would catch it. Or other things like text with the same background color so only a bot could have seen it. Basically, instead of staying defensive, go on the attack?