Just saw this, and i'll respond a bit late. I thought Dumoulin's season was super impressive so that's why for me he's the rider of the year, I could have made the same argument for Thomas or Simon Yates (Viviani's season was very dominant too), but decided to go with Dumoulin for actually his year round consistency.
If Alaphillipe won at the Worlds i'd have chosen him.
If Alaphillipe won at the Worlds i'd have chosen him.