This is an article about note taking, not taking showers or going on hikes, or thinking in general, so I think trying to interpret its points outside that context is unreasonable. I think you’re imposing an unreasonably literal an exclusive interpretation of the point. The author doesn’t say it’s the _only_ medium.
On definitive tone, would the article really be clearer if it constantly went off on digressions about non-note taking contexts to every single point? I see criticisms of articles like this here all the time and it’s really tiresome. If every article linked here was full of caveats and digressions on every last point, they would be unreadable. I’ll take a succinct, opinionated expression of someone’s experience and point of view over a rambling exploration of every last facet of a topic any time.