Your Apple Pay may not need cellular connection or wifi, but the payment terminal of the merchant you wish to buy something from definitely needs an internet connection in order to be able to process your payment.
There are NFC card readers available for vendors who do not have a reliable internet connection at their place of business. The vendor will have to submit those payments for processing once they have an internet connection, but the point is that it is possible for a vendor with the proper chip reader to accept credit card / tap to pay payments "offline" without an internet connection at the point of sale.
Regardless, anyone who travels should carry some local currency, just in case they encounter a retailer or vendor who does not accept any NFC chip "tap to pay" payments or Apple Pay or whatever payment the customer has on their phone. I carry cash at home, and also when I travel.
And tying this idea of always having some local currency in your pocket to the OP question about disappearing ATMs in France or other countries, that is the trend not only abroad but here in the US. We have an upcoming trip to France, and we had no euros on hand from our last trip in 2019, so we bought some euros through our bank (Bank of America) that offers a very reasonable exchange rate, and the euros were delivered to our home the next day via FedEx for no additional charge. How much you purchase in advance is up to you, but I want enough on hand to pay for a taxi, or grab a bite to eat, to avoid hunting for and using an ATM at the airport, and not until I am less jet lagged the following day or so to find an ATM for any additional cash I want to have on hand.