Im am not sure why dynamic pricing would lead to other members of the avios ecosystem to change their own award pricing.
For example, QR already has some simple dynamic pricing. Awards on QR are either Standard or Flexi (2 times). Standard are not widely available in Business.
But these Flexi award cannot be booked on BA program. SUre, you can instantly transfer avios to QR. But BA silver an dabove would not get perks when they travel Y. And then you cannot use avios from a family account. When implementing dynamic pricing, I would assume that BA might only offer the cheapest award to partners in its ecosystem.

One question comes to mind. Avios parked with BA have a significant contribution to its liability accounting-wise and probably profit-wise. Does it make a difference if all BAC members parked their avios with another avios partner?