MSI dropping amd gpus isn't a sign that amd is unfair, but evga dropping nvidia is. You don't sound biased, at all.
MSI hasn't said why, but given the treatment from Nvidia towards some partner brands, assumptions can be made. EVGA was loosing money with the 30 series, and they probably knew what was happening with the 40 series and the melting power connectors.
I have yet to see any proof of AMD prioritizing their own cards over the AIB versions, as Videocardz claims, it would be more belivable that AMD doesn't have enough profit margins to make a significant amount of MBA cards.
However Nvidia being a $3T company could easily produce more FE cards, or buy an AIB to produce FE cards, but obviously Nvidia wants FE cards to be rare so prices stay higher.