At some point in the chain, people need to get out of it. You buy food from grocery store who buys it from wholesaler who buys it from farmers, who could all be spread around the world. How is that feasible without worldwide adoption of USDT?

That's a matter of adoption. These things move very slowly. If you look at the adoption of debit cards, it looks similar. They were first released in the 1960s, and most retailers fought against them and said they would never accept them.

A few years ago there were valid technical reasons for why crypto is not being adopted by retailers in the form of slow transactions throughput and high fees. Nobody wants to wait a minute and spend $10 for their transaction to go through. These technical reasons no longer exist. L2s are extremely fast, secured by L1, and fees are small. And with the upcoming sharding upgrade Ethereum is going to be even faster. From a technical perspective, you could now accept USDT (or any other token) and have verification be about as fast as most card payments, with lower fees. But all of these are relatively recent developments (~1-2 years), and it will likely take a few years before all this technology trickles down into real-world adoption.

The reason retailers don't like crypto is because:

a) It is too volatile.

b) Consumers are not demanding it.

Not sure what the magical solution to either is that hasn't been tried before.

1) Volatility is relative. USD Stablecoins are not volatile compared to the US dollar. It's the same. In other countries, the fiat currency is much more volatile than ETH or BTC. Like I mentioned above, 5+ years ago there was a push for retailers to adopt this stuff, but at the point stablecoins were not around, or unusable due to slow transactions or high fees. That's no longer the case.

2) True, I think the negative image and bad UX of retail crypto is a big reason of why retailers have not adopted it. I'm not sure this will continue forever though.

3) I would add that taxes are another reason retailers are vary of adopting crypto. Depending on the country, dealing with crypto taxes is a pain, and not worth the effort.

The magical solution? It's time, competition, and the free market. If crypto is truly cheaper and easier to deal with, startups will push it onto retailers to replace credit card incumbents. But these things don't happen overnight.

It’s a no-brainer for low margin stuff like gas and groceries. That’s why credit cards offer 10x points or whatever on that kinda stuff. Could totally see e.g. Costco moving off Visa.

At small scale, you can meet up with someone at the coffee shop, you transfer the USDT, he hands you USD bills (this has been a real thing for a while). At large scale you can have large distributors that buy your USDT at an agreed price, and then sell it on either to other large companies or to a distribution network to the people who will at some point buy stuff from you for USDT.

In the end it's a circular economy in a way, for anyone cashing out USDT there is someone cashing in (assuming the price stays constant). Right now we match them up with marketplaces and SWIFT transfers, but people running around with suitcases of cash would work just as well.

Surely you would agree that having crypto wired into the banking system inspires more confidence than “I give you a briefcase full of cash and you give me an entry in a ledger”

You have to have an awful lot of trust that this briefcase full of cash will be available to train back should you ever want it again.