Cruelty of the sport. He wants to secure his future and signs a long term contract last year when he should have bet on himself.
He will be losing millions as he is worth 4 times his current salary.
By the time his contract expires, he may not command a million contract anymore.
It's the thing with young aspiring riders, just like Remco or Bernal, the teams want them to sign as far into the future as possible. And maybe at this age they are not thinking about the money so much.