It's "common knowledge" Jens more or less produces his boards as a side-interest or hobby, rather than making any living profit out of them. He's already apparently quite wealthy. So he's quite able to abandon markets as he likes, whether out of disinterest, boredom, grudges, pettiness, vindictiveness, spite, or any of the other things most people running a business can't afford to make decisions on.

Although the theory he does it for a hobby doesn't explain why he's been so viciously anti-competition through the years.