Interested in a Poco X8 Pro but concerned about privacy

I found an X8 Pro at a great price, but after viewing some reviews, I was struck by the amount of bloatware on the device and the amount of data it collects (even the widgets collect data).

Is this something you see exclusively on Poco phones, or is it a general characteristic of all mid-range and low-end phones?

The phone is for my grandfather, so any custom ROM is automatically out of the question. So I was wondering: by

1. tweaking the settings (I live in Europe, maybe I can opt-out)
2. using an ad blocker (like RethinkDNS) with Xiaomi-specific lists
3. using universal-android-debloater
4. and using open-source apps instead of the system ones

… can I achieve an acceptable level of privacy?

Or is data collection so deeply embedded in the system that these measures are essentially useless?