reCAPTCHA on bridges.torproject.org are impossible to solve for humans

Several users complained that the CAPTCHA displayed on bridges.torproject.org were very hard to impossible for them to solve. For me it usually takes 10 to 20 tries, when I do not give up. The 'H' in CAPTCHA means “humans”. If humans cannot even solve the CAPTCHA offered by reCAPTCHA, then we have a problem.

Can we consider migrating away from reCAPTCHA? Also even if we proxy the queries to Google, not relying on Google would make me feel better.

Otherwise, the problem needs to be taken to reCAPTCHA admins.