In fact, card acceptance has gone _up_ in my experience. Unless you're using a very small shop which just has a QR code, most businesses now use a POS which supports a lot of payment methods including cards.
I agree that a lot of businesses now actively don't manage cash as they used to earlier... it's very difficult to get low-value notes as the central bank seems to be slowly reducing the supply by not printing as per demand.
Card acceptance may be up (I can't comment one way or another) but last I was in India, a large number of POS seem to straight up block international Credit Cards.
Yep, international/amex cards aren't enabled by default by most POS providers (_due to the high fees on the merchant side_) and most small businesses don't really know or care enough to enable them.
I agree that a lot of businesses now actively don't manage cash as they used to earlier... it's very difficult to get low-value notes as the central bank seems to be slowly reducing the supply by not printing as per demand.