Most open sorce licenses do, not just the GPL. I’m not sure what Minecraft modpackers do. But in the free and open source world, you’ll always find that attribution. Sometimes they have a list who wrote the software and who maintained it for what timespan.
Modpacks still have attribution but they likely have attribution to the fork. The fork will have attribution in the source code somewhere but most MC players aren’t likely to actually look at the GitHub repo, so they’ll only see the fork’s name.
Doesn’t GPL technically require you to attribute the upstream anyway?
Most open sorce licenses do, not just the GPL. I’m not sure what Minecraft modpackers do. But in the free and open source world, you’ll always find that attribution. Sometimes they have a list who wrote the software and who maintained it for what timespan.
Modpacks still have attribution but they likely have attribution to the fork. The fork will have attribution in the source code somewhere but most MC players aren’t likely to actually look at the GitHub repo, so they’ll only see the fork’s name.