https://www.metv.com/stories/at-long-last-this-is-the-reason-why-the-smurfs-are-blue

"Making them all different colors would have given them nothing more than superficial identities."

Before she voiced Smurfette in the reboot, Rihanna was a lifelong Smurfs fan (https://www.metv.com/stories/before-she-voiced-smurfette-in-the-reboot-rihanna-was-a-lifelong-smurfs-fan)

The singer expressed her love for the television series!

I didnt really ever think about it.... Blue is a fine coliur for them :)