What's your experience with Android One? First time I hear about it but I'm intrigued, doesn't it come from Google anyway? So the "secure" claims are kind of empty?
Also, direct updates from Google for 2 years without interference from the brand (Xiaomi in this case). Which means I have security updates every month.
I'm not going to buy anything that's not an AndroidOne from now on, with the exception of a Pixel.
You got exactly NONE updates from google. "Android One" has a requirement for vendors to provide updates. All those updates were from xiaomi.
MIUI is baked in and you need to register an account with Xaomi if you want to unlock your bootloader and put, say, LineageOS on your phone. Xaomi has a bootloader lockout period on their phones, during which you must wait and use MIUI for a period until your bootloader unlocks. They've increased that period from what was once a couple of weeks, to over a month on new models. That's plenty of time for Xaomi to harvest your data.
Meanwhile, there are other phones that allow you to unlock your bootloader without a data harvesting period.
Google aims to provide security updates to all Android devices, but specifically targets their product lines (Nexus, Pixel, etc) and Android One devices as they have a little more control over the software.