think1984

To speed up DNF:

/etc/dnf/dnf.conf  
...
max_parallel_downloads=5
max_parallel_connections=20

I have found that RHEL/Rocky/Alma are very much faster at updating using DNF than Fedora, though I don't know why.

I'm older than some in here, I think (judging by the answers). For me, a couple of the things on steakandcheese.com and rotten.com (back in its early days, not the later milder days), cartel videos, beheadings, hangings etc. The standout though was a video called 'Terrorists, Killers & Middle East Wackos'... Grim stuff. From Wikipedia:

Terrorists, Killers and Middle-East Wackos (also Terrorists, Killers and Other Wackos in the UK) is a shockumentary video from the makers of Bumfights. It includes footage of riots, suicides, executions, and the televised suicide of R. Budd Dwyer. All the scenes included are real scenes of death and suffering. The Bumfights website store touts the video as "One hour of the sickest images ever put to film."

I was young and dumb once, but I actively avoid things like that nowadays. There's knowing how things happen in the real world, and there's traumatising and desensitising yourself to the worst depravities possible for... reasons? Just no. You can't unsee some things, and some things shouldn't ever enter your consciousness at all (unless you're really unlucky IRL...).

No problem!

Even Hagezi's most basic list blocks a lot more than OISD, and still no false positives. See a comparison (run over the top 10,000 websites) here.

DNS blocking is heavily dependent on the blocklist(s) you use. It's entirely possible to block >95% of crapware, and break companies' ability to track you without compromising usability.

Having used both for a lot of years, I'd say look instead at AdGuard Home. It is also FOSS but supports more out of the box; including certificate management, the ability to use encrypted DNS both upstream and downstream without need for third party software (cloudflared), the ability to use adblock filter syntax (lists are 200k lines instead of 2 million lines, but actually block more), and so on. PiHole has some improvements pending in the next version, but it's not there yet in comparison, imho.

I'd also strongly suggest you check out Hagezi's DNS blocklists, as they're pretty much set and forget. They're intended to be used as your only block list, and do an excellent job (see testing in the Discussions on their GitHub). Use the Normal list if you don't want to deal with false positives occasionally, and the Pro++ list if you don't mind getting your hands dirty (whitelisting occasionally) and want to block every last scrap of annoyance and anti-privacy crapware on the web. Both will significantly improve your online experience.