The way I tested was search Thingiverse for "angular" and download an STL, then convert it online to an OBJ on the first search result for "stl to obj"

Specifically I tried this rook from this chess set. https://www.thingiverse.com/thing:5994219/files

Sadly, some of the crenelations on top of it are just cubes with 2 sides missing that would be impossible to attach to the folded up rook. I imagine there is a ton of loss between a file for a 3D printer, a random convert to Obj with no settings, and this net maker, so I'm not unsympathetic to the problem. It's just that this is a printout that would not be foldable into something useful.

So weird for me to see this popup now on HN as I happened to dig through an old downloads folder a few minutes ago and saw an install file for Pepakura (13/11/2014), and wondered where that sort of thing had ended up... .

No!

This one is called Unfolder, it's a different app, made by a different person, etc...

More than one app per category can exist, and that's good!

If I built a Mac app, the reason would be that I use a Mac, as do a lot of other people, and native apps are a lot more pleasant than non-native apps. I don't really understand why it's "restrictive"? There is no restriction happening.

The author had to decide between making something excellent for some people or mediocre for everyone, and chose the former

The same could be said about pretty much _any_ software.