I was talking about small businesses like restaurants which generally used to accept credit card even before UPI. Now very few accept credit cards.

Even before UPI credit cards were common accepted online. So I am not sure about that as well.

Small businesses generally dont because the setup for a merchant POS is quite a bit of hassle. In fact maintaining that device also costs money. A UPI merchant on the other hand is quite easy and free from what I know. This setup with visa mastercard might change in the future (with square like devices). However there is also a security problem so fraud might increase with that. Very interesting times for visa and mastercard who have basically not innovated since their existence and yet somehow have grown so big.