1% of the marketshare doesn't send clear signals. At least not ones that anyone cares about.
Interestingly the "install base" is more like 1-2.5% (the number of actual users out there in the wild). There are more users WITH windows 10 mobile phones in % than there are people out their buying new ones in %.
Which suggests that OEMs aren't quite offering the right kind of proposition yet (as well as that UWP is a work in progress). Given the popularity of cheaper models, I think this may partly well be a better speced midrange offering that is missing.
Budget devices are the growing market, and an area with win10 mobile has always done well, but the current offerings both have only 1gb of ram, and meagre storage.
The rest of OEM releases have been focused more on the "flagship" idea, which maybe for HP and the 4s have worked to a degree, but I don't think the gap that seems to be present between "affordable" and "decent" is helping sales.