At least two of those currently have branches checked out with the word "fix" in the branch name. I'd wager that the owners of those forks are using them to fix something, hence "seriously".
One of those two is my fork and yes I did it to fix something, but edandersen's point was more geared towards a real fork (i.e. something that takes the project into a different direction) instead of the fork that GitHub requires to send a PR.
I agree with him, we already have a bunch of popular .NET build tools other than MSBuild like FAKE, basing one off of MSBuild doesn't seem to add a lot of value imho.
People committing to gcc probably have workflows that predate github. I think there are many "forks" that are just done as fixes on a local machine then sent directly as a patch.
Sorry, I wasn't talking about forks the github term, I was referring to forking the project. It's useful to have open source available just for maintenance.
I agree with him, we already have a bunch of popular .NET build tools other than MSBuild like FAKE, basing one off of MSBuild doesn't seem to add a lot of value imho.