Why did MMA/Kickboxing lose popularity in Japan?

I've been a huge fan of the sport for the better part of two decades, and was recently re-watching Hoost vs. Lebanner in the 1999 K1 GP Final.

The stadium was PACKED and the atmosphere looked electric. This was before any sort of social media, so the enthusiasm and love for the sport seemed organic.

When I first started following the sport seriously in the early 2000s, the NYE shows between K1 and Pride would be massive events, often the highest rated programs on Japanese television (I...

Why did MMA/Kickboxing lose popularity in Japan?