Why am I being throttled and not given the advertised performance

I have had to reboot my modem every day for the past few days and/or at least every other day or a few times a week.  It doesn't make sense. Sometimes it is fine for weeks. I disable sharing my network for Xfinity hotspots.
Like millions today - my home is my place of work now and when I called support, they want to send someone. They have been here multiple times. They come and they don't find anything. Performance improves and remains sporadic. I get dropped out of my Teams meeting constantly so I have to jump on my phone's hotspot and is better than my network. I have line of sighe tet to the modem. This is the average speedtest this morning 2/11/2021 around 8:30a.m.

BEFORE REBOOT:
Download speed 0.1 Mbps
Upload speed 0.7 Mbps
Latency 67 ms
Protocol IPv6
Host Secaucus, NJ (why did it go to NJ instead of Chicago? I am in northeast Indiana)

Reboot the modem through the Xfinity xFi portal.

AFTER REBOOT:
Download speed 0.3 Mbps
Upload speed 0.8 Mbps
Latency 65 ms
Protocol IPv6
Host Secaucus, NJ (why did it go to NJ instead of Chicago? I am in northeast Indiana)

0.1 to 0.3 download and 0.7 to 0.8 upload speed. Impressive? NO. This is not what i am paying for.
This has been my issue with Comcast on and off for years.