Warning Signs?? - no!!
This isn't new news. Some years ago, some European jurisdictions moved to adopt GPL applications such as Open Office rather than be tied to the MS Office suite with its multiple licensing and security issues (as well as the associated expense). Others have moved toward the adoption of Linux OS distributions for both desktop and server environments for the same reason. Many of us have gone through the trouble of creating dual-boot laptops for the same reasons. The program to develop an affordable laptop for developing nations decided against an MS architecture for the same reasons.
But back to Lumia where this all started; the "market" will drive the future of any set of devices based on capabilities, cost, and perceived usefulness. Android and iOS both offer capable apps and relative ease of use. Some of their platforms cost more, but W10 mobile's future is being shaped by its growing irrelevance in the market especially where new hardware and associated capabilities of that hardware are concerned.