It just means keeping track of the difference between empty dopamine, which rewards behaviors that don't benefit you, from dopamine which is working in its normal evolutionary context--to encourage behaviors that do, and being intentional about how often you engage in the former.
"Digital hygiene" sounds like the start of a mental framework with good intentions, and which might help somebody with their World of Warcraft problem. But that problem isn't really unique to digital things, they're just a commonly found example of it. If you have a habit of seeking out empty/fast dopamine loops, where the rewards come frequently and are otherwise useless except as a reason to continue the useless behavior, then you're likely to come off your World of Warcraft addiction and immediately find a (potentially non-digital) addiction to put in its place.
My point is that yes we need a new kind of hygiene to deal with modern kinds of manipulation, but no we shouldn't restrict its scope to computers. I watched the video, but it's pushing back against something altogether weirder than my point here. I don't see how this counts as "manipulative disinformation," or is in contradiction with established science about the function of dopamine.