It's a fair question I've tried to figure out myself, and while I cannot speak for the devs or the rest of the community, here's my take from a non-dev outsider looking in. I think you have to consider that when this coin launched, more crypto seemed to be going after being a payments related alternative, unlike today where more coins and tokens seem to be launched trying to solve a myriad of other/different problems.

I guess the better question might be, do we need so many coins that have a primary function of payments, and my opinion is the more the better and let the users decide which interface, functionality, and community they wish to embrace. The cream rises, but there can be many dominant players in a marketplace. Think cellphones, or IM messaging apps, or soft drinks, etc. Those who keep innovating usually keep rising, and that's where I think the OKCash devs and collaborators greatest strengths lie. (see ROKOS for an example) Do I wish sometimes there were more tools or apps being rolled out to utilize OKCash more/better? Absolutely. But I also understand that OKCash probably doesn't have these huge coffers to pay an army of full time developers (at least, I don't think lol), and that this seems to be a labor of love for everyone involved, and that says something...at least, it does to me.