I believe its because they A-B tested his thumbnails, editors found that they vacuumed slightly more eyeballs when he was smiling, and updated the thumbnail images of him not smiling with photoshop.

The fault isn’t with the photoshop though, he just doesn’t have a soul so it actually looks like that when he smiles.

https://github.com/SatoshiNT0 Satoshi really got into emojis, I guess?

🌱 I’m currently learning … Quantum Cryptography.

💞️ I’m looking to collaborate on … our world!

Cool.