For my nuyen, an "action" would be anything requiring a Free, Simple, or Complex action. So Full Defense would be an action, while basic Defense would not.
However, some things just don't always make sense. Spam zones affecting Full Defense, okay, maybe the ads are distracting you from the real dangers, but it feels like a stretch to me. Confusion affecting Damage Resistance? that one doesn't even hold water from a common sense perspective.
That's where GM's come in, to decide when "all action"/"all test" modifiers should be ignored in favor of immersive storytelling.
But, I don't think you're going to find an official ruling, odds are there are GMs who would consider "all actions" and "all tests" to be synonymous, I know I nearly did when I first started reading the rules.