No, they're not different. If I can't sign away the title to my car, it's literally worthless. Exactly the same is true of my IP rights.

They're inherently different: creative work (especially in a digital, trivially replicated format) is non-rivalrous, and at least partially non-excludable. "You wouldn't download a car." [0]

Property rights are a social technology to balance incentives and peacefully negotiate scarce resources (including time and effort). It's helpful to think about them in reverse: that they encode legitimacy to use force (usually via the State) against anyone who violates the right. That doesn't make the force right or wrong, a priori; it simply describes what happens. Exactly when that force is legitimate is the question at hand.

"Intellectual Property" is a post-hoc neologism. What we actually have are three very specific institutions: copyrights, patents, and trademarks. The last is arguably more like regulation than property: persistent brand identity to prevent fraud and confusion. Copyrights and patents are extremely clear in the Constitution, that their purpose is collective, moreso than an individual right for its own sake: "To promote the Progress of Science and useful Arts". Hence why they expire: at some point, the incentive has already been provided, and the body politic benefits more by their being open-sourced.

Whatever "rights" framework one subscribes to, it is an extremely thorny question, whether they include the right to alienate those rights, to give them up on purpose. We allow people to alienate their labor, an hour at a time; but not to do so for a lifetime (voluntarily sell one's self into slavery). Many US states now refuse to defend "non-compete" clauses: that you cannot constrain your future self from working for a competitor for X years, even if you wanted to, even for very lucrative terms in the contract.

I'd argue that intellectual/creative works, are more like non-compete clauses: you actually create more bargaining power if you limit the scope, and take away the capacity to give up future bargaining power.

[0] https://www.youtube.com/watch?v=V_gZZHu4TBk

They're absolutely different. IP rights are a creating of artificial scarcity for what would otherwise be an infinitely-copyable work. Physical property rights are a codification of rights to a naturally scarce item.

IP rights require specific limitations on speech for everyone who is not the owner of an IP. It's walling off some expression as "copyrighted" so that no one other than the "owner" can express them (in a commercial way at least). Compare this to traditional property rights that merely prevent you from walking up to the owner and taking their (non copyable stuff) - a much lesser restriction.

This is why IP rights need to have limitations like a time limit, but I don't see why other limits like non-transferability are out of the question.

What? Car leasing is a massive market, and a large percentage of people and companies are very happy to pay to access cars and trucks without owning the title. Same goes for companies happily building on top of leasehold properties whenever it makes financial sense for them.

And as for IP, with the time limits, patents and copyrights are inherently defined to expire, but are definitely not worthless.