Ok but it’s only an imaginary concept until somebody wants to take your stuff.

"Intellectual property" is a fiction not bound by any sane laws of reality.

Meanwhile physical property is bound by the fact that you can't create new matter.

I think that's a little broad, IP should be divided further into:

- is there value in keeping it secret / not public? (e.g. commercial software, etc.)

- content, things that can be freely distributed without diluting the inherent value of the property

In the first case, I think it's analogous to not being able to create new matter. Once the secret is out, you can't put it back in.

In the case of content, I'm a lot more open about this but it does bring up all of the tricky questions of ensuring that content creators get paid for their work, etc. (another endless debate)