I use Mi9SE with eea rom. After update to MIUI11 phone is bugy as hell. Battery draining fast, hotspot and bluetooth not working properly, apps crashing, camera app living their own life and etc. MIUI 10 was better, but with some bugs too.
After 6 months, I can definitely say, sorry Xiaomi that was my first and last experience. Tech specs are nothing without a properly working soft.

The article writer must want Xiaomi to push buggy updates, all oems push to selected devices before a full roll out.

Huawei have just pushed an Android 9 update whilst still rolling out 10.
Reason:     December security patch
So why the clickbait title?

I bet if we check all oems to see who has the most devices on any type of Android 10 Xiaomi would be at least third.

I'm running a Mi 9T which is still on Android 9 Pie with MUI 11. To be honest I don't care one iota if I don't receive the Android 10 update, the phone works so perfectly on Android 9 I would be worried the update would have bugs to iron out so I'm happy to leave things exactly as they are.

You will get proper updates when they are released. China ROMs are always updates first, they basically act as the beta before it's pushed to global devices. Instead of complaining, simply unlock your bootloader and use the Xiaomi.EU rom. The Coding is 4 to 6 months ahead of the global rom and it's an all around much better experience. Plus, it has many features ported from the Pixel. In my opinion, it's better than Miui and any AOSP rom combined.