People want to hold assets with disinflationary or deflationary supplies, because part of the promise of those supply curves is they should store value well.
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The burgeoning "collateral economy" around $ETH is amazing to watch, and allows ETH as a SoV to extend its utility far beyond what it could hope for as a pure MoE.
Meanwhile, $ETH as a PoS-based SoV will be the internet's "on-chain" collateral (endogenously secured).
Simple psychology.