Blockchain isn't really the solution there, though.

I don't want a public ledger with all my payments, which tells not only what I consume, but also how much I am able/willing to spend.

And as soon as you are in massmarket you need ways for humans to intervene, for handling complaints, mistakes, whatever or dealing with the unavoidable case that individuals lose their secret keys. Or even cases like medical restriction or inheritance requiring others to take over the funds.

All those things Blockchain purposely and inherently prevents.

You can just send a transaction from your exchange.

Like, let's say I want to send you $0.10 right now. I would just go into Robinhood and send 0.1 USDC to you on Polygon or Solana, that would arrive in your wallet instantly from a Robinhood-owned address, you would have no idea who I am or my previous transaction history. Robinhood also owns the private keys and account recovery process here - it's just using blockchain as the payment rail.

Go ahead and post your address and I'll send you $0.10.

Okay, so the solution is to use a bank, not Blockchain money.

But you can't send $0.01 instantly and anonymously with bank rails. The solution is to use a crypto exchange on crypto rails - just not a regular crypto wallet (you could, but perhaps not very user friendly)

Isn't that just turning the exchanges into unregulated banks?

Many exchanges are regulated, but maybe not as banks. But yes you're trusting that exchange with your money. If used for web-micropayments it shouldn't be much of an issue though.