I've never been able to see the hand icon ever since and no one else seems to have documented its appearance. However, after some searching, I was able to find [1] (archived at [2]) which should serve as sufficient proof of this existing and not something that my mind hallucinated out of those "drink a verification can" memes.
(For people trying to visit [1], you should copy the square brackets at the end of the link, which HN leaves out when adding the anchor tag.)
[1] https://google.com/recaptcha/challenge/hand-gestures?d=[]
Seems to be working if you percent-encode them:
https://google.com/recaptcha/challenge/hand-gestures?d=%5B%5...
It's likely easier to generate a matching photo these days than process some of the visual captchas. So it would be pointless to implement.