Justified in their concerns, certainly. But not in their seething, frothing paranoia.
We have people comparing the installation of a near-stub browser add-on by the browser vendor, to full-on home invasions.
The language was a mistake and should have not been pushed out, or maybe even written to begin with. Mozilla ought to remember how skittish their userbase can be.
Even though the add-on itself was innocuous, the context around its scope, delivery, and presentation were not what they should have been.