Leeds Approach you say:
LBA and DSA would not 'need' to close at all in exactly the same that Teesside doesn't 'need' to close. It is called solving the problem with the best answer not any old answer. Having too many airports is the worst possible answer to the problem -it creates problems not solves them and hence massive passenger leakage. 1 person on a flight to Belfast clearly shows this. Free market forces just like anywhere else in Europe. Not only that but you are NOT able to say what is 'likely' as you are completely in the dark as to what has potentially been agreed in the long term between certain parties.
Totally contradicted yourself in the opening few lines.
However you are right in that lots of airports aren't needed and you clearly show a lot of jealousy for the size of Manchester Airport. Fortunately airlines aren't there for you to spend their money so they will operate where the best returns are. I totally understand wanting to have decent access to the world and what that brings but reality has to kick in and a new airport isn't the answer.
Infrastructure is and in the case of Sheffield they want much better access to Manchester airport not Leeds East.