Wow, that last info I wrote actually made me fix the issue. I use this RPi for pihole as well, other devices use it as a dns resolver with no issue (RPi’s IP is the main router’s primary DNS), and when I tried pinging a couple times from the device, I always pinged 1.1.1.1, 9.9.9.9 and so on. I just tried pinging deb repository and got an error.
In diet-config, IP of this device is static and x.x.x.20, meanwhile DNS IP was set to IP of default gateway which is x.x.x.1
As soon as I switched static DNS to x.x.x.20 it started showing traffic on pihole and status “Working” for trackers announce links.
I’m not sure should I mark this as a solution, or wait for @Tarrasque to fix his as well.