It wouldn't even occur to me to pay by cash in a supermarket or garage. I automatically reach for my card (as I would be doing even if Covid hadn't come along). So I'm not getting cash refused, simply because I never proffer it in the first place.
Prior to Covid, the only places I used cash were at the local burger van, at the launderette, at the barbers and in some car parking machines. I now use apps on my phone to pay for my car parking and the launderette now accepts cards. Losing most of my hair through chemotherapy means that I've not been to the barbers since before Covid but, when I do finally get back there, I'll be surprised if I can't pay by card (as I'd prefer to do anyway). The only place I still need cash is at the burger van (where the owner sprays all notes and coins upon receipt with disinfectant and again when handing them out as change).