Meta/Facebook preinstalls an app called Meta Services (previously Facebook services) on a very large percentage of android devices (I've never used one without it) and while they claim it helps updates and synchronisation between different meta apps, it is very suspicious. Why preinstall it on devices of people who will potentialy never use a single meta app?
Go to your app list/app management and show system apps and find anything with the words "meta" or "Facebook" then turn off network access for those apps (if you can) and disable them. (eg. Meta app manager, Meta app installer).
Edit: Looking around I have found several people complaining that this app is using their ram for 10 hours a day even though they don't use anything Meta. That's even more suspicious.
It's not unlikely to be an NSA thing which allows them to access everthing. That sounds paranoid, but Snowden happened so we know they were doing stuff like this 10 years ago:
DROPOUTJEEP .... "A software implant for the Apple iPhone that utilizes modular mission applications to provide specific SIGINT functionality. This functionality includes the ability to remotely push/pull files from the device. SMS retrieval, contact list retrieval, voicemail, geolocation, hot mic, camera capture, cell tower location, etc. Command, control and data exfiltration can occur over SMS messaging or a GPRS data connection. All communications with the implant will be covert and encrypted."
To be honest, I think we just have to accept privacy is dead. The only real choice that remains is whether to regularly teabag our phones on on the off chance someone's looking.
Shit like this is why I use a DeGoogled phone. Get a Pixel and install GrapheneOS or CalyxOS and use open source apps wherever you can, and sandbox any Google Play apps you have to use (banking, etc).
One of the pros of using a Pixel! Absolutely no bloat on my previous 4a or my current 7 besides a T-Mobile app that was installed because of my SIM card. Uninstalled that and I was golden.
All the phones I've had come with bloatware like this, I currently have a Xiaomi phone and MIUI itself is bloatware, the ROM is full of ads. Thankfully there is an "adb" software for Xiaomi phones that allows you to disable or remove this pre-installed malware.
Of the cheap Samsung, LG and huawei phones that I've had they also come with random bs pre-installed that can't be uninstalled without the help of third party software.
Ugh, stuff like this is why I bought a pixel. I got an s23 for "free" from T-Mobile, and it was so infested with spyware and bloat that even android debloater couldn't get it all.
GrapheneOS has basically made it all worthwhile. I do with I could have multiple (more than 2) profiles though.
I'm so glad I went with a Pixel 4a. Main factors were the smaller size, but I also chose it over the cheaper Samsung alternative because of the OS. Stock Android is just nice, because then you only have to worry about the Google bullshit and not also all the other bullshit on top of that.