One thing that the Naruto franchise did better than most other shonen series was its incredible cast of villains. They were deep, complex, and brilliantly written, and made the series even better by challenging the heroes not just in battle but in their ideals, such as in the case of Naruto and Pain. However, not all the villains were well received.
https://screenrant.com/narutos-controversial-final-villain-was-actually-good-for-the-franchise/