I was thinking about this and was wondering if the transformer was
on its way out, anyway, or if the generator presented an open neutral
situation on start-up. Maybe a combination of the two.

I had a messenger cable break at one of my old homes, and without
actually getting up on the roof and inspecting it, one would have
never noticed the break. Anyway, pretty much every non-protected
wall-wart in the house fried. Thankfully, the important ones were
on a UPS. I could care less about the phone and the foo foo crap
in the bathroom. :-)