There are many conflations in these statements of yours, but one of the more offensive is that corporations are responsible for an individual's open-source contributions because that individual draws a paycheck for something else. What's the corporate equivalent of a bootlicker? An NDA-licker?

What I don't get is how someone can hate companies like Oracle, wish that they would disapeer out of the face of the earth, and at the same time jump of joy when a couple of lines get added to the Linux kernel, by the corporation they want to nuke.

if they offer it under gpl, it's no poison chalice. why do i care who does the right thing? what's good is good.

i would be more worried when they propose that we all abandon this adequate gpl tool for this permissive licensed code they seriously didn't write, but here's ten fantastic contributions they made.

It is not about being a posion chalice, rather the attitude of wanting to nuke company X, while accepting whatever it gives as gratis contributions.

I only see that among FOSS folks, seldom among other kinds of activism.

Because of the nature of the GPL. You don't get those guarantees in most other forms of activism.