No yahoo doesn’t have any plan to go away anytime soon. but yes! I agree there service quality is getting poor day by day. Not only you, there are so many users complaining about email problems every day.
Meanwhile yahoo support team is not focusing on customer service team appropriately.
Do to which, many people have also moved themselves to other service providers like- Gmail, outlook or aol. if you are also facing the same problem, you can also look for another better option.