I'm curious why you think this. There's been several attempts at a Googleless Android based phone and as far as I'm aware none have achieved noticeable market share. At least not the kind needed for Huawei.
Huawei is allegedly opting for an android based OS. which takes off the biggest drawback of alt OS, android app compatibility. you can just side load via apk a normal app and you are good to go (given zero dependency on GS etc...)