Wifi is turned off.

I checked system updates.  Last update was January 2024. and phone says all updates are current.

Bars. Right now, I would estimate 2 bars, maybe 3.  It doesn't separate bars individually like I have seen on some phones.

It was suggested to download Network Cell Info Lite app.  I have done that. I opened the app up. on the 2 guages it shows, it shows -110 to -120 on the guages. I don't know what this means.  This does show this is in the "yellow zone", as opposed to the green zone, or red zone.

I did a test on download and upload speed.  Right now, download speed is 9.3 mb/s; upload speed is 921 kb/s; on Dec 22, my download speed was 1.6-1.9 mb/s; upload speed was 593-693 kb/s.

I did look at the article you linked. I didn't find it particularly helpful, as the reviewed spent a lot of time on screen layout, camera function, etc, which I am not too concerned with.