Even if they develop a mobile OS, will it be the quality and usefulness of Google services? Android is just linux + google services. Without those, it's hard to make the sell to western audiences, at least.
Google Maps is a masterpiece of engineering and it's hard to imagine that Huawei will be able to compete, near term. If I'm reading the situation right, this might mean the end of Huawei in the western phone market unless something changes.