Sure, maybe sometimes you get a weird one and fail it. But typically the next challenge is easy to pass. Seems the author cherry-picked some of the worst reCaptcha examples for the article, but wrote it in a way that made it seem they were presented back-to-back.
Besides this -- the article makes no attempt to offer a better solution.
Captcha's are really the best way we have right now to "prove" someone is not a bot. Hidden Form fields, etc, don't work and are easily spoofed. Sure Captcha's can be beaten by bots sometimes -- but I trust Google's scale/volume with ReCaptcha to handle that for me (for the most part).
Captcha's are not going anywhere anytime soon.