Well written. You tapped into some fundamental problems.
Lets assume Splinterland is Noise, just a outlayer, then Hive would have no marketshare. How could Hive redefine "NFT" in a way that Hive gains market share? Is the cheapness of dPOS really all we have? If so, we directly compete with Solana, Avalache, or L2 like Arbitrum. What is with the proof of brain aspect?
The points like cross-chain compatibility/tradeability are deffensive strategies. They defend against the point of becomming obsolete. Onchain-ness and onchain composability is high entropy domain. No rational agent would have a layer 1 NFT (autoglyphs, loot) on a chain B that is less secure than a Chain A. What could be a offensive strategy where people have to move to hive/layer2 in order to have a unique NFT expirience?
There is a very real way that all posts and comments on HIVE are NFTs. The permlink name space is finite and unique. Proof of brain does tap into this... However, Hive's proof of brain-ness has been diminished almost to the point of proof of participation. Proof of brain should be moving to layer 2, just like tokens should exist on layer 2, with NFTs as well.
In many ways I agree with you about portability being a defensive measure, but the number one defensive strat is for scaling.
I'm not sure you're familiar with dlux.io ... my dApp front end for hive. It has full proof of brain, fully decentralized, and is capable of doing anything that I've ever heard suggested. I believe the cheapness of dPos and the ability to make dApps on chain that can just as easily serve as creation/management tools, as well as games/experiences that can use NFTs available at API endpoints to be a beacon. Of course, this is all just code that can be copied, modified, and run anywhere... and that's the most common problem in the space. There really can only be one SHA PoW chain, but that's determined by the hardware capital. PoS is a different beast entirely. Economics of computation space and efficiency are the product you are selling, the lower the barrier for entry the higher the adoption.