You're confusing your idea of what a photographer does with "photography" as a subject. Photography is an incredibly diverse hobby and profession. Yes, it is possible to only buy one small subset of equipment that lets you photograph a single very specific things well, but I've never met a photographer with such narrow interests.
Even professional photographers that only do a specific kind of photography professional nearly always have amateur interests in other photographic subjects that require different gear.
Far from it, you can also have video games as a hobby and use a 5 year old laptop. A teen that can only afford one camera is not necessarily less into there hobby.
I have even known someone to go the other way and sell off there kit for a point and shoot. They where into candid photos so always having a camera was more important than fiddling with a massive beast.
Granted, camera's are cheap to most of the HN crowd, even blowing 30k over 20 years is just not a big deal. But, just because gear is 'cheap' and 'better' does not make it necessary.
From the equipment list provided, it sounds like portraiture is the goal--not photographing bugs. I don't see where it is implied that the poster is trying to boil the ocean with regard to their photographic pursuits.
Consider, nobody says you need an electron microscope to get serious about photography, but they can take some amazing photos even without using photons...