You have a point but only in the case when you have what to sell. Does a new team have players to sell at high price? No.
Increasing the FA agents number is one good thing that was done.
I expected much more from the tax they put on rich teams. If it was more rigorous it would have a better effect and in my opinion in just 2-3 seasons prices would go down. Why? When you have much money and someone tax it, you spend the money and yes, in the first couple of seasons prices would be crazy but doing that you start the wheel. And then it comes to the moment where you sell, you buy and more teams have 4-5M instead of 1-2M but on the other hand you have (as it is now) many teams with 10-15M.
And of course we know that almost everyone loses from transfers so what happens to the money - they just got spent (first thing) and they are also circling between teams (second) but not staying focused in some teams.
Now, as you say many managers don't buy players because they are too expensive compared to their quality, so what you need to do is make these managers spend their money. How? Tax them.