So my thought is that Elon has a net worth in the hundreds of billions. He clearly can and is willing to manipulate the price of Bitcoin (and receives no negative consequences for doing so). If he even hints that he might integrate Bitcoin into Twitter, the value of his Bitcoin (and likely Twitter) holdings would skyrocket.

Now, why not use lightning directly? Because there are costs to every transaction, which for lower-value zaps are very high in percentage terms. Also because the tax implications and complications are astronomical -- see this nostr post from a single individual.

Ecash allows Twitter to be a mint. It would be "trusted" because it's a big company (have the tech to prevent rugs and bugs, and are reputationally incentivized). Plus, the tokens would only be valid on Twitter.

Twitter could then license other companies to use its mint, and could charge users fees to withdraw to sats, and more fees to withdraw to local currency.