Perhaps. It's also important to note that the areas where we can spend the money we save by ignoring the possibility of signing high-profile players in favour of developing our own are rapidly shrinking. Previously, money we saved could have been spent on infrastructure: now, we've pretty much reached saturation with the state-of-the-art training complex, youth academy and stadium. We could spend it on wages, I suppose, but I'm dubious about the extent to which we'd puff up our wage bill just to reinvest the money we save from not buying high-profile players (if we do go down that route).
With the new stadium and PL revenue coming in, we'll have a lot of surplus income we'll have to put somewhere. It's also doubly important to note that developing players long-term is also no assurance of success when short-term buying can just as easily propel you into title/CL contention (a la Leicester). It's just that the margins have become smaller all around: in the old days, signing a superstar (like Aguero, for example) would instantly take your team up a few notches, whereas now it seems like the advantage (which does still exist) is more marginal. You can still gain advantages doing it, of course: it's difficult to imagine, for instance, that a team that goes out and suddenly buys Batshuayi, Aubameyang and Lewandowski (to take three illlustrative examples) wouldn't experience a boost in goalscoring after those purchases, whatever the equally frenetic activity of the sides around them. And those advantages are still likely to boost teams like ours up a few notches: it's just that the marginal utility of these buys is now in decline.
It's more complicated than just developing our own players in an age of new-found sporting equality, I suspect. It might come down to eking the marginal value out of the buys we make, however high-profile they may be: while that's hardly a conclusive, philosophical answer, it might possibly be the only firm assertion we can make about this seemingly waxing trend.