I've always thought he meant he would not spend all his budget on one star player because it would unbalance the team, and make them over reliant on the star player. He would prefer to build a team to be able to play together where one player being injured or simply not playing well does not impact on the overall performance.
Where he said if football became this way he would be out of a job, I believe he was saying an over reliance on 1 team member would make the coach almost irrelevant compare to the star player, like messi/sampaoli at Argentina.
I think the whole quote is long winded way of saying if he had a £100 million pound budget, he would spend it multiple very good players and not 1 star player.
I could be wrong of course, but that's my view.
Easy there Sarah Sanders.