dnf took 5 min or so to install htop
If you’re talking about download speed, dnf may use incorrect mirrors to download pacakges (by default, fedora use metalink to give dnf mirrors according to your ip address, unlike other distro; I once find it trying to connect to really far away onces, even timed out after 30 seconds). You can try sudo dnf clean all to clean caches and make sudo dnf makecache to force dnf make its cache again, and (hopefully) dnf will pickup faster mirrors again.
Alternatively, you can setup mirrors manually. Edit repos in /etc/yum.repos.d/*, comment out metalink= , and fill in mirrors you find in baseurl= (either search by a search engine or manually find one in https://mirrors.fedoraproject.org/), normally you want to edit fedora.repo fedora-modular.repo fedora-updates.repo fedora-updates-modular.repo (edit further rpmfusion repos if you enabled rpmfusion).
Very strange - and it’s not just FF. Evolution took about 10 mins to return a password request on a new account setup
If it’s ff, gnome web, evolution and not everything (unlike the case in After Fedora 33 update; kworker/u32:2+events _unbound killing my cpu - #15 by huscape where everything is crazily slow), then it may all due to the #1913390 redhat bugzilla.