The curve is the mouth. Blue thing resembles the Hitler stache.

I was in the same boat. They changed it so quickly I didn't even notice the "problematic" one.

It's the blue tape that changed, not the "smile".

To be fair, the tape reminds me more of the orange hair patch of a Mr. Meeseeks than Hitler's mustache, mostly because of the smile. The only way I can see a blue Hitler mustache is imagining a closeup cropped from below the nose, and a really tiny mouth.

I guess it costs them less to change the icon and letting the self-offenders pick someone else.