I think this is where people will disagree with you most. There are many threads full of worried 4E players in the 4E forum that hope the changes being made to the game with Essentials don't change the game too much.
Then you have people that were unhappy at the outset of 4E because there was no gnome, druid, barbarian, monk, fill in the blnak with your other favorite missing element, etc. Many of the elements are now in the game.
And 4E is the most malleable edition to date. New concepts fit in well because of the modular exception-based design. Things have changed since its inception and it seems valid to ask the question. If you don't like the question, don't read the thread. Easy enough.
Ok, since I don't play 4e if it's that susceptible/open to change I'll take your word for it. However, you appear to be talking about more than your typical rules expansions. For the changes to be so significant to bring back "those who left" at this point, you'd almost have to be talking about changes on a scale of a new edition.
I do seem to recall quite a few threads/posts stating that Essentials didn't invalidate the hardcovers, wasn't 4.5, not that significant, etc. etc. Granted, I only skimmed those threads so perhaps the changes are more sweeping than I thought.
If we
are merely talking about expansion, then my question stands. The edition has grown but hasn't changed enough to warrant a new edition. If you saw features as flaws, chances are you still do. If DDI's subscription model didn't grab you, that hasn't changed. If you loved the OGL, WotC hasn't dropped the GSL and gone back to the OGL, etc.
As I stated earlier upthread, I understand wanting to influence the publisher - esp. when a new edition is on the horizon. It's the seemingly incessant need to "recruit to one's side". The RPG landscape is a much rosier picture than I'd have predicted 3 years ago, hence my assertion that the Edition Wars are over. Mindshare has been gained (by one publisher or another), games have been selected, etc.
Based on several other threads (here and elsewhere) I've been following of late, I'm thinking the real answer is people just like to argue on the Internet. What they're arguing about is a secondary consideration (and a distant one at that).