So, while Samsung may ship Tizen and Windows Phone, they may not build phones for Amazon (which caused Amazon a lot of problems back in the day - where will you find a company making portable electronics that will make them a white-label product and not making android phones).
2. MicroG depends on Google's servers, so Google can pull the carpet out of them at any time. And where will you get those millions of apps if Google doesn't let you access the App store? Look at the difficulty Amazon has at getting apps into its store, and it's a larger company willing to pay devs to switch apps to Amazon store. And all the hacks that people use will be closed by Google once they get popular.
Now sure, you can use MicroG as a porting library (so if I have a closed source app relying on firebase I can trivially switch to relying on MicroG and Mozilla's back end - kind of like wine), but you'll still have to recreate all of Google's apps anyways (there's no way Google will publish their apps on an Android fork) and also those apps written by those who don't care to port (unlike wine - where I can use the OEM CD or EXE from the OEM website, there's no official way to get apks out of Play Store)
As for Play Services, they could just have a team whose job is to make MicroG work exactly like Play Services so that all apps work including the Google apps.
The only Google app that you need to replicate is the Play Store client (or really, the downloader, since you can just use the Play Store website for the UI) and then the user can install all the Google apps from the Play Store.
As for getting developers to put apps in their store, it's certainly much easier than getting them to write another app.
Instead, they could have gotten all the Android apps and the popularity of Android essentially for free.
It's even possible they could have overtaken Google and became the effective steward of the Android platform, since Google doesn't offer a version that can be installed by users and also doesn't offer their version to OEMs with no strings attached.
Again, they still can do that now, since there still isn't a version of Android that runs on any phone other than LineageOS, which is relatively underfunded.
[obviously what Mozilla would gain from this is market share for Firefox for Android]
On the other hand, I'm already a KaiOS customer because they power the phone I want: the one that makes calls and handles text messages, and then gives me a high-speed network for my computer. I spend about a quarter of my time in India; while there I got a Jio phone and liked it so much I found a KaiOS device that works in the US as well.
No they wouldn't have. They would not get Google Play Services and your MicroG "solution" is ridiculous from a commercial perspective and a violation from a TOS perspective that would be shut down by Google.
>It's even possible they could have overtaken Google and became the effective steward of the Android platform
I don't think you understand the army of developers it takes to maintain and enhance Android on an annual basis nor the millions of dollars it costs Google. To even suggest that they would have overtaken Google and become the steward of the Android platform is ridiculous.
If I have Firefox and thus can load up any Google web page, do I need Google Play Services?
There's no point in having Android if you can't run Android apps, and most Android apps users want are now dependent on Google's proprietary libraries (Play Services). So why would you want an Android fork if you aren't going to be able to run Android apps? Might as well go with KaiOS at that point.
If one does want or need native apps (e.g. for security), then is it possible for a third party to emulate Google Play Services? Or do they use a certificate to prevent third-party clones?
Why would they need to acquire LineageOS when they can just fork it for free?
>worked on MicroG to reach feature parity with Play Services
That would have been a TOS violation and would have been instantly shut down by Google.
>their own app store
You can't really compete with the Play store and developers wouldn't bother with it.
>they would have had significant success at very little cost.
No they wouldn't have. It would have reached the same outcome as their Android based FireFox OS did and even faster due to the TOS violations your suggesting.
If Mozilla had simply acquired LineageOS, worked on MicroG to reach feature parity with Play Services, added Firefox for Android and their own app store in addition to Google Play via MicroG, and resold flagship Android phones with that as well as offering it to OEMs, they would have had significant success at very little cost.
In fact, they still could do that.