> Yes. If I really _want_ to execute malware on my device, I should be allowed to do so by disabling the antivirus or disregarding a warning.

I agree.

> already the rule of law in "sane" jurisdictions, that manufacturer and mandated warranties are not touched by unrelated, reversable modifications to both hard- and software.

Do you have any examples of such jurisdictions? I think whether this is reasonable turns on how "reversible" is interpreted. If it means "reversible to factory settings", including wiping all built-in storage media, then it seems reasonable to me that manufacturers should support this (possibly modulo some extreme cases like cars that have dozens of CPUs). But I would not be happy with having my hard disk wiped if I sent in my laptop for repairs because a couple of keys stopped working, which tells me that (to me) there remain at least two classes of "problem that should be fixed for free under warranty by the manufacturer".