All Important?
The "all important" Google Play Store may not be that important, especially in the light of the recent anti-trust filing against Google by the DoJ.
The busines reason for using Andriod and Google's services is the business reason for shipping PC's with Microsoft Windows. Both are adequate solutions for the software for these devices, both work just about as well as they need to and at a price point which makes it not cost effective to develop an alternative. Alternatives do exist, though, and are likely to be technically better because they can learn from the existing dominant systems. All that's needed is some kind of market push to get some traction for any alternative, say a large manufacturer with a large and motivated user base, and its likely to become a serious competitor.
I tend to think that the US government's actions over Huawei are likely to do far more damage to Google than their anti-trust suit. The suit might keep generations of lawyers gainfully employed but actively encouraging a competitor -- a motivated competitor with a motivated customer base -- has the potential to undermine core segments of Google's business (as well as damaging the basis of the anti-trust suit -- after all, there are alternatives.....).