I think this misreads the situation. The problem is that the distribution of players skill against value isn't linear. If you look at individual sports ranking lists you usually get wide gaps at the top and then everyone bunches up lower down. The very biggest clubs hoover up the best players and we get stuck with those just outside the elite who are not much better than those below them. Man City's skill edge over us by spending twice as much money on their squad is much bigger than ours over clubs who spend half as much.
If there is an edge to be had in coaching we've tried most things already. If our objective is to supplant one or more of the really big clubs we need more than a slightly better coach.
I think you’re saying similar things to me here. Spending more doesn’t guarantee success but having more resources makes you a more attractive proposition to players and selling clubs as you can offer higher wages and transfer fees. I think coaching is a bigger edge than you imply here and this is demonstrated in the table right now.
Ultimately unless you have the resources of a City, sooner or later the players and managers get taken by the wealthier clubs. And like you say the money effect definitely scales. But money means very little if you’re not using it well, and with vision.
