Even if you're the taker, the seller would still verify outside of, say, Bisq that the funds are indeed received, then confirms on Bisq the receipt. Bisq would then release the funds from the escrow address to yours. That's on-chain. Again, it won't be instant.
Yes, you seem to be correct here. That process would normally take some time, at least if the ATM company doesn't offer some intermediation or handle the escrow itself, but then we would already probably be in KYC territory.
However, there would be a way to make it a bit more instant: if sellers can signal their online status (so the buyers would take only orders from those who are actually online at that time) and agree to verify a new ATM transaction in let's say 10 or 20 minutes (otherwise to be penalized), then it would be already much more acceptable for the buyer.
And if the seller reacts slower, the ATM would only transmit them the code when they have accepted the transaction. So the buyer can go away without having to worry about his money, he would get it back if the seller cancels the transaction.
Not to mention that while you're paying in cold cash, the other end of the trade would be receiving money via a bank account.
A design involving a bank transfer from the ATM company to the seller imo would not have many advantages regarding a "traditional" ATM, because the ATM company became involved in an exchange directly and would have to obey regulations for exchangers.
Otherwise, if your design in mind would be implemented, which is for the "seller would get a code for the ATM and would have access to the compartment where the buyer deposited the cash", that would be more implausible, at least right now.
I would not frame it that much as an alternative to a current ATM. That kind of "automated cash locker" machine would be an alternative to in-person meetups, and some issues that can go wrong in that kind of meetup would be less likely (e.g. counterfeit money or the seller running away with the cash without transferring the BTC). Of course that needs trust in the machine vendor/operator.
I could imagine such a machine in hackerspaces, Bitcoin cafés or similar places.
I'm not sure if you're familiar with Satori Coins. They're Bitcoin-loaded chips which hold a private key underneath a holographic sticker. They used to be offered in a gashapon in Japan. It's a vending machine. [...] the current level of Bitcoin's adoption, however, I'm not sure if this could still be done without AML compliance.
That sounds cool, I didn't know that exact kind of "offline bitcoin", but yes, I think your last sentence nails the problem: as it's custodial, at least in places with regulations similar to MiCa the service in the present would have AML obligations.
Your response seems inadvertently cut.
Oops. Don't know how that happened but I corrected it (anyway in my response to odolvlobo I made a similar point).