Hardware wallets and self-hosted Lightning have been catastrophic for the adoption of Bitcoin as currency. I think this is what we're finding out.
You don't spend money you've put on a hardware walle...
Your CD analogy is the tell — CDs are the savings tier *by design*; what's missing is a checking tier, and that's a UX problem, not a key problem. Submarine swaps + ecash = the spend layer. ETF analogy misfires — ETF = claim with counterparty risk, keys = ownership.