I've never experienced what the writer has, and it would be interesting to know more about their system setup to diagnose the alleged network slowness. Package manager is a network app, so it sounds to me like there is something strange going on system-wide. Perhaps the writer has a new-enough network card from a vendor that doesn't have driver support?

FWIW I am essentially full-time Linux on all my devices for the first time in my 20 years since first using it (Ubuntu 6.06). The only issue I had is with a wifi card that is a brand-new spec without Linux support - I happened to have another wifi card that has a more open chipset that is also wifi7 that works great.

Here's my quick intro to anyone interested in running a Linux machine for gaming and everyday use.

https://docs.zeropolis.net/doku.php/tech:cachyos

I've actually experienced this, but I don't know if it's related.

In my case, installing linux on a laptop and while everything was fine, there was an unexplained network delay. What ultimately fixed it (and I really don't know why) is I had to fix the time on my system clock to the right date/time and then got ntp setup and working correctly. My system clock was far in the past. I THINK (but don't know) that the root cause was in certificate validation. Perhaps hiccups because the certs were issued in the future?