I've had a brief look around and it seems fine for me.
Arch Linux
The beloved lightweight distro
So probably it's about my network. Thanks for reply.
The Arch Wiki (and possibly other Arch websites, but when I checked I wasn't able to catch it) uses Anubis (https://anubis.techaro.lol/) to mitigate AI crawlers causing issues on their servers. Anubis works by making your computer do some computations before being let in. For users like you and me, it'd be a minor inconvenience, but for these AI crawlers, it'd cost them a lot of computation as they hit these sites a huge number of times.
Using Anubis is said to be a nuclear option, but as these AI crawlers don't care about that, sites, especially FOSS ones, started using it.
Because it has to be recompiled for every update.
Wouldn't that be Gentoo's website?
Oh I understand it now. Thank you for information.
Website, or package repos? Two different things.
Website.