The idea of stockpiling seems to be out there in the now, even without any guidance from the government. I went to our local Tesco yesterday for various bits, and the tin aisle, and the UHT milk aisle were both very busy. I've also not had a snarky comment from a till person in months now, despite buying tins. (Last summer I had several laughy, dismissive "you're not hoarding for Brexit, are you?" comments.)
I've mentioned the idea of preparing for potential shortages to my closest friends, but as they both ridiculed the idea, I didn't go into it in detail, and didn't feel it's my responsibility to convince them. They can read, they can make their own minds up, they can do their own personal risk assessments and decisions. I do worry about elderly MIL a bit, who is an avid Leaver (Farage is a wonderful man and things will be better, you'll see), but both physically and financially frail. I'd still prepare myself to help her, but we don't live close enough that we'd actually be able to physically help, if she suddenly needed it.