This largely matches my understanding. NEXT is supposed to be 5.x, until then it still has APK compatibility and AOSP compatibility (no Play services of course).
> And I am skeptical about the HarmonyOS Next thing and can't see how its fate could be different from Windows Phone if Android apps are out of the question...
Their approach is a little different than throwing something new at the wall and hoping it sticks and I actually see it working. E.g. HarmonyOS 4.x can and does already run non-APK Harmony apps, it just also runs APKs. This is why the article notes the growth of native Harmony apps prior to Harmony NEXT even launching - the transition already started. This also means Huawei has had time to do things like have the existing nweb (Chromium based browser) port while working on ArkWeb (in house browser) to replace the outside dependency wholesale. The browsers are great examples of the progressive strategy - slowly build more independent options over the years at the same time you slowly replace the backend OS over years and now you've done all of these "impossible" things without ever having the "big moment" replacement people can easily reject.
Such a system would be, at a fundamental level, better than Android and IOS.
Are you forgetting WeChat? Because that's all they likely care about.
This needs a lot more context. My understanding is that at this time HarmonyOS is still fully compatible with Android and you can just install apk files like you would do on any other Android device. They are doing their own stuff at low level, and it is reported that "HarmonyOS Next" will be incompatible with Android (no idea what that will look like), but to say HarmonyOS 4.2 is "not-Android" means as much as saying Amazon's Fire tablets are not using Android.
And I am skeptical about the HarmonyOS Next thing and can't see how its fate could be different from Windows Phone if Android apps are out of the question. While it is true that China itself is a huge market, and there are enough users and developers to demand an "in-house" OS, there are a few obvious, big hurdles -- app ecosystem, browser etc. Of course Huawei can throw money at the problem and get developers on board, but one needs to be aware that (1) there are only about 3 big browser vendors in the world, and even Firefox and Safari are lagging in features and bug fixes (2) even in China Huawei needs to compete with other phone makers who are using Android, and developers need to support Android, iOS and Harmony OS. I am not optimistic about this.