I've seen quite a bit of thís on here lately and find it quite unpleasant. If you're living with someone who's extremely vulnerable, the thought of them getting covid 19 is bloody terrifying. Their chance of dying from it is much higher than the average person's, and the thought that they could die alone and frightened is heartbreaking.
So yes, even if there's minimal chance of them getting it from plastic or cardboard or eating a takeaway or whatever, it's still a chance you don't want to take.
I totally get that some people will have different opinions on the need to wipe down groceries, quarantine post for 24 hours etc and that's fine. But to those who post in a sneery or patronising way about these precautions, maybe show a bit of consideration and empathy.