I get what you are both saying, but it's far too simplistic to boil it down to transfer fees.
For example, 3 of ther top 6: Crystal Palace, Middlesbrough and Watford have success which is built on a spine of youth graduates and then Watford have a plethora of loans they've got through their relationship with a very strong European club.
Now, don't get me wrong, I'm not excusing that, as personally I feel our academy is shocking and our record of producing players compared to other clubs (such as those 3 and the likes of Southampton and to a lesser extent Cardiff, Swansea etc. not to mention Crewe) is quite frankly embarrassing. However that's hardly something that can be blamed on the current manager or previous managers when they've only been at the club a year or two, you can't build a good academy overnight. Quite frankly that's been a fundamental problem at the club for years and has been something that's meant we've had to buy in more than the likes of Boro, Palace and Watford have. Jon Rudkin has been here a decade now and I'm still not sure he's been good for the club.
That said, the jury's still out on Pearson's signings. I think Pearsob's biggest problem is that he's bought for the long-term not the short-term. It's difficult to tell whether Marshall, Knockaert and Drinkwater are value for money yet because they're just potential at this point. Morgan I'd say has definitely been worth the money so far, but De Laet and James I think we overpaid for.