The Boring Company is not a failure. It's actually a major success, for Tesla. It successfully led a generation of politicians and journalists think that there's no need for public transportation, that Elon Musk will solve all our infrastructure needs. It's a modern day GM Streetcar.
California high speed rail (the only real attempt at high speed rail in the US) didn’t need Musk to kill it, it killed itself due to incompetence in building quickly and affordably. This is a shame, because an actually affordable, working high speed rail system in America would be amazing, but won’t happen until we learn how to build again quickly and affordably in America. And who knows how to do that? Elon Musk!