Except with debit the risk is now back on me to make sure my PIN doesn't get stolen/skimmed/whatever. Transactions are less convenient than a single tap, and (at least in the US) requires paying attention to see if places even support debit.

Ironically, many smaller shops don't support it, even though it would theoretically be cheaper per-transaction, because the up-front costs and hurders are higher than a Square account.