Thinking about this more, my first response was so incomplete as to almost be a lie.
You *cannot* know reality. All you can know is a model of reality. So when you say "reality" you're actually using a abbreviation for "in my model of reality".
And when I said "physics is physics" I was so oversimplifying as to almost be lying. Consider "flat earth" vs. "spherical earth". How do you know which belief to accept? The direct sensory data seems to imply that "flat earth" is the more appropriate belief. There are lots of arguments that "spherical earth" is a better model, but those are nearly ALL based on accepting what someone else says. We are told of experiments we *could* do that would validate it, but very few people have, themselves, done the experiment. So for just about everyone the "spherical earth" model is a "social reality".
Similarly I accept that I have a spleen, but I do this because others have told me it's true. I'm also told my tonsils were cut out, but I was unconscious when this was supposed to have happened, so I'm taking other people words for it.
Reality, as we know it, it largely a social construct. We don't know just how completely it's a social construct, but that's hugely what it is.