I can already see that fork collecting dust on the shelves of mtb bike stores everywhere. Only ones that would sell will be at a 75% off clearance price.
Changing the rake dynamically as the fork compresses is not good for predictable handling. The reduced rake as you go deeper and deeper in the travel will make it slower steering at bottom out. Look at motocross bike with long travel, they always have constant rake throughout the long travel for predictable handling...