To clarify, when I say "most people", I mean, "most people who are XXers" (where XX is runners, calligraphers, music-makers, etc.). Example: while "most people" don't do penmanship (and don't need the tools of trade, obviously), "most people" who do penmanship will have specialized "gear". That's my point: to have a hobby that's more than a passing interest, "most people" will acquire "stuff" that is critical to that hobby.
(Aside: very sad statistic on U.S. runners.)
In this case, it makes sense.
Though one could argue (given the clarification you've made) that said XXers could also embrace a minimalist aesthetic.
E.g. electronica makers: do everything in the box, or with very few pieces of kit (minimal gear). Penmanship: just use a couple of really good pens and some select stationary. Etc -- and of course they can keep the "minimal stuff" in all other non XX areas of their lives.
"Most people" in first world countries hardly ever run.
The official statistics I've seen put "joggers and runners" as 17-18% of the US population, and their definition includes all the "people who went jogging or running within the last 12 months in the United States" -- so in reality, much much less, especially after school/college age. This makes those irrelevant for the 80% and more. In most first world countries, which don't share the US obsession with jogging, that's substantially less.
As for "Penmanship, quills and ink", that's not even a thing for the overwhelming majority of the population. At least not since 1950.
And "making electronica"? I happen to do that, but I can count on one hand the number of people I know who even know what Roland or Ableton are (apart from collaborators etc).
So, I'd hardly call this list representative -- if it said "urban hipster" maybe, but the "for most people" qualifier is totally bogus.