Improving the store of value functionality of the Ethereum base currency will drive more demand for it, which increases its market cap and thus improves Ethereu

Improving the store of value functionality of the Ethereum base currency will drive more demand for it, which increases its market cap and thus improves Ethereum's Proof of Stake security, makes more capital available to the DeFi system, where ETH is the primary form of collateral, and allows more inflationary currency that's backed by ETH, like DAI, to be issued. Also, most Ethereum based projects depend on ETH reserves to fund their operations, so ETH appreciation provides more resources to develop Ethereum applications.