My iPhone supports transit passes even when the battery is dead. I don’t think this is an intractable problem and indeed the designers of NFC designed for this problem: the NFC payment system provides the juice required for the SE chip to do it’s thing.

QR code as transit passes aren’t great but eventually the worse designs will fade out. NFC is a way superior piece of tech and way faster too - just tap your phone and go. I was pleasantly surprised that transfers worked seamlessly this way too.