You grossly overestimate Googles ability to support an OS on multiple platforms. Do you remember the why Samsung Galaxy Nexus was abandoned? Apple supports iOS

You grossly overestimate Googles ability to support an OS on multiple platforms. Do you remember the why Samsung Galaxy Nexus was abandoned? Apple supports iOS on two platforms (32-bit and 64-bit A-series). Microsoft who has been in the OS business much longer than than Google only have resources to support Windows 10 Mobile on a handful of carefully chosen Qualcomm chips. So basically the only way this could work is if Google would create their own SoC and mandate Android vendors to only use that SoC. I don't think Samsung would like that too much.