For the longest time, this model of frame was left unwanted and un-noticed.
The type of specs you see on the Dahon speaks for it self. (as with the more boring color options; Fnhon offers more interesting looking colors )
It rests between the high portability of a Brompton or even 16" bi-fold and a larger / "faster" 20" folder.
Heavy too being chromoly.

Then sometime around the covid years, maybe people lacked bikes to buy and some folks got the Fnhon Gust and managed to bling it up and popularity soared.

You can probably find a Fnhon over the usual China websites (eg. AliExpress)