Again, it is not a failure of him or his project that his development process heavily relied on him reviewing, modifying and merging patches and that he at times did not commit time to do that. He was not obliged to do more than what he did and vim was indeed very successful.

However, it is also very understandable why vim was forked by the neovim devs, in my view it has been a great success. That doesn't diminish Bram Molenaars achievements and contributions to the world.