Let us look at one example of a real property.
The cat is black. I.e. I can see that the cat is black. And now comes the joke. All of you doing scientism as per real do the same. You conflate 2 different versions of X is Y. In effect you treat the following 2 versions of the verb "be" as the same.
The cat is black is the same as science is the methodological study of what's real. Indeed what real is, is real as what the cat is as per observation.
But it is not. The cat is black is not the same as the cat is real. And what science is, is that it is several different cognitive behaviors in humans, and that is not the same as what the cat is, even for the word "is".
I could go on, but I won't. Either you learn that real is not different than in effect ethics. It is a norm for human cognition of what some people claim matters more than something else.
Yes, saying that a cat is black is saying that the cat is within the type (or set) of black objects, which is loosely defined by absorbing a large portion of photons. When I say that something is real, I am likewise saying that it has the type of real, under formal type theory, which I prefer to set theory due to its applications in computation.
Ethical values are not real. Cats are. Black is not real, but it is a way of categorizing real things. Blue is real, however, because it refers to photons travelling within a certain range of wavelengths. Blue is not a property, but instead refers to a specific kind of light.
Things are only "real" in so far as they are concrete, natural, and physical. Black does not fulfill that criteria. A screen can look white in a dark room but black in a bright one. It's not a property of the object itself. When blue is treated as a property, it's a relationship between an object and the photons that touch it, specifically that it reflects mostly blue light while absorbing most of the rest of the natural color spectrum.
It's not about what "matters more." It's about what objectively exists in the external world that we indirectly perceive with our imperfect senses. Even if you're a solipsist, you have to admit that there is a different quality to the objects you observe with your senses than the sensations you imagine or visualize. Namely, you have no control over them. That lack of control is enough to call it "external" as in "external to your direct control."
It has the appearance of self-consistency and, through induction, we can demonstrate that it is as real as we are and is indeed self-consistent. We can't prove this absolutely, but this is a problem that's been resolved enough since Descartes.
I'm not having this argument with you again, though. I don't think you instigate these arguments over reality and knowledge in good faith, as if you were just dispassionately making the best arguments you can for epistemic non-cognitivism or solipsism. I'm beginning to seriously suspect that you just want to deny reality so you can believe whatever you want.
I can't stop you, but that's irrational. Literally irrational. The rationalists are the ones who helped show that external reality probably does exist.