DECT-NR competition is 802.11ah and BLE Long Range. They all provide moderate bandwidth and moderate range, up to 1-2km. I bet they aren't low enough for battery-powered sensors, but probably good for battery-powered devices like Wifi or LTE.
My guess is that winner will be whoever get cheap devices out, and leverages their ecosystem.
Unless I am mistaken. Is that really the case? Both 802.11ah and BLE Long Range operate at lower frequency and also lower bandwidth, higher latency etc. DECT-NR could do everything the two could but not the other way around.
While 802.11ah does operate at sub-1GHz, BLE Long Range seems to be 2.4GHz, just with much more robust coding.
DECT-NR on 1.9GHz wil be lower in frequency than that and on less shared spectrum.
The comparison is not the same everywhere, as the European 868MHz bamd allows much less power (25mW vs. 1000mW) and much less bandwidth (5MHz vs. 25MHz) than USA 915MHz.
Similarly the USA 1.9GHz DECT band allows less power (100mW vs. 250mW) and less bandwidth (5channels vs. 10channels) than the European band.
So even before meshing DECT-NR has some major advantages over 802.11ah, in Europe.
My guess is that winner will be whoever get cheap devices out, and leverages their ecosystem.