The author doesn't like that it is written in tcl/tk. I have no idea how this would matter at all unless he plans on modifying the source. I happen to like gitk and use it often. What language it's implemented is of little concern to me. At one time I used tig(it is pretty old at this point), but it never really caught on for me. Perhaps I didn't give it enough of a chane, perhaps it's much better now.