How you got so may SOT if your details are almost without any activity....you said firewall, which do you use?
AFWall+
I allow only selective apps that I use, all the rest blocked.
And I configure the system for minimal background traffic, I only allow whatsapp. Telegram X (very high consumption) with no background data, only works when I open the app, when I close it, the app is off. This you can configure in "Battery & performance" > "choose apps" and restrict background activity for apps with a high consumption.
Other important thing, is the auto start apps. And disable automatic google play updates, if not, google services will be all time searching updates.
I hope this help you.