This was my fear when TV money started increasing. To my understanding the reason we managed to sign a lot of the players we did was that we tended to bid more than other teams for them (Mane, Wanyama, VVD, Gaston off the top of my head). This made us the selling clubs preferred team as they got more money. This meant that we didn't have to compete with other clubs when it came to wages as we tend to offer less than our "rivals". With the TV money going up unless we switched our bidding in line with inflation or whatever you want to call it all the teams would match our offers and we would struggle to attract the players ahead of them as they offer more money.
I'm not really blaming the board about this, just saying that our old model of chucking a couple of mil onto what everyone else was willing to offer isn't going to work now as £20m isn't a big fee anymore. Times have changed from a few years ago and we need to either change with them or find a different model.