ianl_person
With blanket immunity, law enforcement remains the responsibility of government agencies that (1) we pay to do those jobs, (2) have due process requirements, and (3) have broad immunity within the confines of their job. Without blanket immunity for platforms, we're requiring them to take on law enforcement responsibilities with none of the usual protections in place.
Banking secrecy and KYC laws are, I think, a great example of how consumer-hostile this can be.
One possibility I like to think about for PCs is replacing usernames with a root of trust (hash). A trusted ROMed hypervisor downloads the configuration (or loads from cache) and netboots.
But ultimately it's bigger than PCs. Embedded computing is becoming pervasive and allows easier monitoring and control of what people can and cannot do. Today people accept that owners or manufacturers can set whatever policy they like even if it's user-hostile.
Users often aren't the owners of their computer. Currently that means the computer may act against the interest of its user. I'd rather have a world where users can trust their computers even at the expense of the owners' control.
While a physical ME switch is vulnerable to physical attacks, it does seem like the best approach we have today for minimizing owners' ability to subvert the user.
So if the reciprocity clause in Facebook's patent grant is a problem, all recent MIT licensed software out there without a patent grant would also be off limits.