The game is currently imbued by the Dev's own vision of what a golf game should play like (Links plus) - minus some technical limitations imposed by the Steam/Unity/Speedtree ecosystem. In short, they are doing their own thing and to heck with whoever has issues with that.
Selling the game or teaming up with a publisher would instantly bring the suits into the mix, you know, those bozos who worship the mediocre mainstream and want to feed it dumbed-down morsels and cash in on DLC like +4 Accuracy Gloves or + 5% distance drivers: JNPG would not be about being a golf sim anymore, but about the number of copy being sold and the percentage of market penetration.
I do not see the Devs signing up for this: They will never willingly give away control over what is their own baby. And they will keep evolving it as quickly as they can, i.e. as slowly as they need with very limited resources. In this day and and age, I find such an attitude commendable and endearing.
Poking the bear IS a valid motive for starting this thread - but that bear is very secretive and this poke was, um, a bit obvious.