I don't quite understand what peoples issues are.
Eddie is looking at his team and obviously isn't happy with some of his options in some positions. Taking Scum Half for example, he clearly isn't happy that the players he's looked at, apart from Youngs, are good enough, so he's looking at his options. Are people suggesting he should take player who he doesn't think is good enough, just because they have been "around the squad for the last few seasons"? If they have been selected but haven't made the grade in his opinion, then surely he's justified in not continuing to select them?
People bitched about his support & continued selection of Mike Brown, then when he dropped him, moaned about that too.
I don't agree with a lot of his selections, but then I'm not the England coach.
And all this "players must be really upset if they haven't been selected".... these are young men who have spent most of their life being selected, or not, for squads, at school, for clubs, for districts, counties, regions and countries. If they are upset because a coach doesn't think they are good enough, they would have packed up the game a long time ago.