I gifted my mom a Xiaomi phone a few years ago. Even after removing all the unnecessary apps and permissions, disabling all the privacy invasive settings and replacing the launcher with the stock Android, I was shocked when I checked the PiHole dashboard. The phone was constantly trying to communicate with dozens of different domains and endpoints, even when idle. None of these attempts had any sort of backoff, so they kept retrying every 30 seconds, draining the battery. Ultimately it generated several times more blocked requests than every other device on my network combined.

This was the first and only Xiaomi device I ever bought, no matter how attractive they might seem.