I don't necessarily care about moving a valid session to other hardware as much as I care about being able to create a valid session on any random hardware without having to trust any 3rd parties or rely on any 3rd parties permission.
TPM would be fine if 2 things were true:
1 Only the end user managed the secrets inside. Or at least they could, and without any penalty like "This device is insecure and so you can't use it for X". It's fine if there are default secrets and most people never change them. I'm not sure about this last bit but I think ideally also any factory default secrets should be erasable, no indellible unique serial number.
2 The interior implementation is fully open and disclosed. How the secrets are generated and managed. Not just a description and a promise, but an actual full set of public specs such that any manufacturer can produce a fuctioning device, or even I could out of other parts.
These things would allow the end user to be benefit from the mechanism, while leaving the end user in ultimate final control over their property and their identity and information. And it requires both. 1 is hot air without 2.
Any objections to this are automatically invalid, as they depend something they have no right to.
"I need to know that your computer is not doing something I don't want." is just fundamentally invalid.