I don't think this phone is a threat to the Pandora as the Pandora is a mini computer, but it is a huge kick to the Dingoo, Cannoo etc. I think the days of those machines are very very limited now.
Smartphones are definitely a threat to the Pandora, even without gaming controls. You don't need complete overlap of functionality to consider them as competition. Once the preorders are fulfilled, I hope you can attract some fresh publicity to let people know that they can buy one without any wait time, and a few changes to the website to emphasize the openly developed firmware, flexible OS (i.e. this page, but more pictures), and the full size USB slot, so people can more easily understand why they would want to choose it over a smartphone.
And I'm all with you on a standard interface on emulators but alas it seems several devs will resist that until the death which is a sad situation.
It's unfair to the developers to be levelling an accusation like that. I think all of them agreed with you that it would be a good idea, it's just that it would take a lot of well-coordinated work to make it happen.