You’re free to hold your crypto on an exchange, you’re free to buy a hardware wallet and do your due diligence when confirming transactions, you’re free to create a multisig for your coins and tokens to introduce multiple factors for signing.
But it’s your choice.
people dying, losing keys
That’s on them, it’s like stuffing money into a mattress and not telling your family.
mining coins are destined to die
Mining’s not great for sure, but “destined to die” makes no sense.
Inflation is necessary so that people spend the thing
That’s kinda funny, because in the case of Ethereum, the deflation comes from people using and spending Eth on gas.
I’m also not saying that Ethereum is the perfect currency to replace fiat, the utility there comes from everything that’s built on top of it.
Widen your horizon, crypto isn’t just a medium for payments.