All these proliferation of downloads that you speak of are the hard work of dedicated people offering you and others within the FS 2 community photo scenery, cultivation, special objects and accurate mesh totally free of charge.
Yeah....... And if you look at the number of downloads, you will see that they are very small. Maybe twenty people doing so. Why do you think this is the case? I suspect it's directly related to lack of installation directions, or confusing directions. I often post links to interesting Aerofly freeware of various forums, yet some I simply can't in good conscience recommend because it simply requires too much effort of people not inclined to be intimately familiar with Aeroflys folder structure. The tendency of said files to be in multiple and sometimes redundant downloads from more than one person ups the difficulty and probably partially explains why you see nobody posting videos of these creations. Too confusing to even install them!
Your suggestion of "pulling it together" into a single download is absolute nonsense as the folder would be so large those with slow internet access would be prohibited from using it.
And why is it absolute nonsense to have a large download available in a sim where all of the available payware and most of the freeware comes in large files such as Florida, the Netherlands, etc. If these files were unacceptably large, Aerofly itself (which just with the Freeware from Ipacs itself exceeds 100GB) could not even exist.
Lastly it may of been a kindness to at least thank those for their dedication to our hobby.
I have actually been one of the few that more than once has explicitly thanked the creators multiple times, so don't even go there.