I think you will take heat for this one. There are plenty of reason
brake pads will squeek for none of the reasons you mention. Some Hi Perfs,
Carbon/Kevlar, will squeek until up to operating temp, some will squeek do
to resonance between pad binders and caliper housing (ask any vintage Vette
owner Me!), some will squeek from vibes between pads and caliper pucks.
Some metal based pad will squeel during the metal on metal action and some
will just sqeel do to build up of brake dust, etc etc.