Like you pointed out, there's a fundamental difference between the transfer of a bitcoin, and the transfer of a token that represents a claim on some external-to-the-blockchain property. In the later case (asset-backed tokens), all that is transferred is ownership (and ownership is really a social construct, valuable only to the extent that one's society is willing to enforce property rights [as control of the property in question remains a physical problem]). In the former case (bitcoin), what's transferred is control itself.
Thank you. This is brilliant stuff.
Going back to this interesting area. Agreed with above.
There seems to be a greyscale in the amount of the social trust needed to enforce off-blockchain rights, depending upon the type of asset involved.
An example where the blockchain token can have good control in the physical world is where physical keys exist, such as car keys or house keys. If physical keys are made smart, activated by a verification signature from the same private key which controls the recipient bitcoin address, then cars and houses can respond only to their new owners. Usage rights pass with the bitcoin transaction.
This is not watertight as physical locks can be changed, but the principle exists for the blockchain to hold access to some external assets, particularly other digital assets.