Ethereum's security is not how much eth is staked, its how hard it is to control fork choice. A curve that goes to 0 at a reachable level will allow the biggest and most price insensitive orgs in the space to price out the vast majority of rational actors, such that they can control who gets to use Ethereum going forward. The original curve deliberately prevents this, by increasing issuance as staking ratio goes up, making it impossible to price people out. Cappers will tell you this was a bug and mistake, it was not. Ethereum should focus on CROPS, not wanting to have a security budget crisis faster than bitcoin does. I'll share more about this in the coming days and weeks, but tl;dr: decentralisation > hard money.