The two big things that QR codes have going for them is that they're cheaper to make and that they can be trivially displayed on a smartphone screen.
Contactless ICs are more powerful in every other aspect: They're rewritable (allowing reusable tickets), they can support challenge-response authentication (allowing secure offline usage, which in turn makes for faster transactions at the gate), and they're much less finicky to scan in my experience.
Contactless ICs are more powerful in every other aspect: They're rewritable (allowing reusable tickets), they can support challenge-response authentication (allowing secure offline usage, which in turn makes for faster transactions at the gate), and they're much less finicky to scan in my experience.