My guess it's more along the lines of the problem of marketing the new shiny to new users or new projects vs supporting the existing users. In a perfect world, they would build the new shiny and their existing users would switch (which it sounds like they keep pushing for) and their hopeful new users would be happy seeing the new shiny stuff.

The real world means you have to support both for some long period of time, because your existing users won't and many times can't switch because of myriad reasons you didn't think of, and if you can't both support the old and build the new, you have problems. Like this.