Wow, that quote from my site must be 15 years old or more at this point, LOL. Fast forward to the present and some things have certainly changed. Still, newcomers to the hobby might find the perspective put forth in that quote to be irritating. And yet, it was 100% true and honest based on my experience at the time.
One point I think many did not (and, perhaps, still do not) understand is the fact that, back in the day, the only way to find that mystery greeblie on your favorite starship was to buy a bunch of old kits and go through them piece by piece. If you were lucky, you might have at least some idea of what you were after (i.e. "it looks like a part from a tank"). Modelers experienced in certain genres could recognize certain details as being from a particular type of tank, truck, car engine, etc. But, we still had to take a chance buying what might have been a very expensive kit(s) in the hope we might find the part(s) we were after. If not, that money was wasted and it was time to try again (and again, and again, and again). I remember one fellow telling me he'd spent over $400 trying to find just one part. That adds up real fast and many of us ended up spending many thousands of dollars collecting kits trying to find the right details.
That was *before* people starting posting and sharing kit lists online. Back then, if you were looking for an old kit you might have to bid against someone who collected old race cars, or old tanks, or whatever. Once studio-scale modelers joined the search, the competition for rare kits increased and the prices started going up quite a bit. This is the main reason IMO some people got protective of kit info.
Today things are changing in that we now have "libraries" of kit scans available. This makes it less risky financially to locate mystery parts because you don't have to take a chance buying these kits thanks to the generosity of those who bothered to purchase and scan them and then post the scans online. Eventually, all these parts may get "digitized" and it won't matter anymore because you will be able to print what you can't buy. Until that happens, however, it can still be hard to find rare kits and it can be very expensive to acquire them when you do find them.
The bottom line is it still takes a LOT of work (and sometimes a good bit of money) to make an accurate replica. It's not just finding the parts, it's also finding a way to get the shape and proportions just right. I liken this to an artist creating a "portrait" of their subject. Unlike a pencil drawing, however, getting a good likeness of something in 3D can be very difficult. It will be up to those doing this hard work to decide what it's worth to them and whether they want to release that hard work to the rest of the world.
Things have changed a lot over the years, and it's probably easier now for new people to get started in studio-scale modeling. The information out there now is far greater than what was available back in the day. You'll still need to do your homework, but if you dig deep enough you'll find lots of "Cliff's Notes" and other types of "cheat sheets" available to help get you going.