They relaxed the restrictions on CTAs a while ago:

"As part of our efforts to continue delivering quality stories to our readers, we’re loosening some of our restrictions on story elements that don’t have a major effect on overall story quality. These include many restrictions on headlines (except clickbait), reasonable profanity in headlines, clap requests (and other benign calls-to-action), and crowdfunding asks."

Source: https://link.medium.com/ytaRXees8eb