#GitHub's proprietariness has always been an unseen landmine, but like its predecessors #SourceForge, #GoogleCode, #CodePlex etc, projects have chosen based on present convenience (FOSS friendly, zero or low price for non-profit projects and individuals, large numbers of users --> potential for drive-by contributions). However, the big issue with GH and the others listed above was that to some degree, they were the center of gravity for code-hosting in their respective time periods.
#DVCS software such as Git, Breezy, Mercurial, Fossil, Darcs, Pijul and so on could be used to enable a much more distributed hosting model--and should be. If people and projects do not have to join a specific #code-hosting site in order to contribute to a project / attract contributors, the allure of sites like GitHub starts to fade.
Correction: #Pijul ... it is a #dvcs / #scm system written in #Rust, and an evolution of some of the ideas behind #Haskell's #Darcs, including fleshing out the theoretical basis and solving a couple of major bugs.
If you’re interested in !TclTk, then you may find #jsish interesting, because its internals are designed based on some of Tcl’s internals, and because it integrates the #Fossil #DVCS and can be updated using standard Fossil commands.
I think y’all know I favor the #Fossil #SCM / #DVCS over #Git (though I’m giving #Mercurial ( #Hg ) another look as well. I’m resource-constrained as well as energy-limited, but I have been thinking of standing up a miniature software forge for !FNetworks projects and users, likely using Kallithea (which can use both Hg and Git) and also having some Fossil repos (but not as part of a forge).