Something people need to understand: real anonymity is really, really hard. Your COMSEC is a fairly small portion of the attack surface area, and the consequence of this is that staying anonymous is, BY NECESSITY, going to be very inconvenient.
From this perspective, captchas are a very minor concern. I'm as pro-privacy as anyone, but this expectation that anonymous activity is supposed to be easy or convenient will never be satisfied. Thousands of years of lessons from both military and civilian clandestine operations bears out the critical lesson that anonymity is, by default, very very inconvenient. Nothing is going to change that.
Agree, though pointless systems that likely extract the identity of a user, force them to work for free, etc - and fail to counter the risk they supposedly stop is abusive.
From this perspective, captchas are a very minor concern. I'm as pro-privacy as anyone, but this expectation that anonymous activity is supposed to be easy or convenient will never be satisfied. Thousands of years of lessons from both military and civilian clandestine operations bears out the critical lesson that anonymity is, by default, very very inconvenient. Nothing is going to change that.