I tried to follow the guide and add dependency to my build.gradle but the link is dead.

Can confirm, I've released my mod a few days ago with version 1.19.4:4.1.1 and it compiled just fine. Opened the project now and gave it a gradle reload, Indeed it no longer finds the jar. Althought it seems is only for the fabric jar, I've done the same thing in Forge and I got no issue

EDIT: not sure if is related or is another issue, but the discord redirect link(https://discord.geckolib.com/) is also broken (you get a "DNS points to prohibited IP" response)

Can you confirm if this still occurs?
We had a brief period where the Maven repo was down, but this should be rectified now