I think some might well be forgetting the importance of what some of the more experienced players bring in terms of when they're not in the starting lineup.
Some of these players who are passed their best or who don't make it into the starting eleven are a vital part of what galvanises the team during big moments and when the pressure is on.
You only have to look down the road at the Cauldron of Piss to see that it's not as easy as saying "this player is better than our current one" and binning ours off for someone else's.
The winning mentality, willingness to show support to a teammate who is their rival in the starting eleven and all those other intangibles are not as easy to find as looking at a player for a couple of games and saying "he's got a nice first touch" or "he's much better defensively."
It looks like we're going to be losing various players who are important to the mentality of the squad as a whole and I think it's going to be harder to find adequate replacements than some seem to believe, even if the players we're after are in their physical prime.