I’m running a Framework laptop with 32GB of RAM, an AX200 Wi-Fi card, an Intel i5-1135G7, and two terabytes of NAND storage, on standard Fedora 37 (i.e., not a spin, just the default GNOME DE and all). I normally have downloads speeds on my home network of 50 megabit or higher and upload speeds of 5-10 megabit, but for whatever reason at seemingly random points in usage, it seems to go down to 5 or less megabit per second download speeds, with upload speeds being unaffected. I had the same issue before when I was on Fedora 36, and I also know that it’s not an issue with the Wi-Fi network itself since it happens on other networks and doesn’t happen to any other device on my home network.
Note that F37 (rawhide) is not currently released. Since you say you also have the issue on F36, we can discuss it here briefly, but ideally all rawhide discussion happens on different dedicated channels:
Is there a reason you are using rawhide instead of F36? (Most of us on the forum here will not be using rawhide, so it makes it harder for people to try to reproduce your issue etc.)
The issue sounds like a hardware driver related issue. The kernel wifi page suggests the driver is iwlwifi:
The first thing to do is to look at your journal logs to see if anything is printed there when you notice the drops in speeds: