Barastrondo, death does not appear to me quite terribly hard to find; I have had a 4e character come within one point of it in one round, and seen another character buy the farm thanks to "friendly fire".
But that's not really so much of a 'consequence' if (as suggested in the 4e DMG) a replacement character is going to be of "party level", whatever that happens to be whenever it happens to get built.
Heck, considering how comprehensively the 'build' dictates factors, it's close enough to automatic resurrection! (YMMV on the 'identity' question, of course.)
Really depends on the players. At one end of the spectrum, you're absolutely right: one game token has been lost, and can be replaced with another token, one which may in fact be better optimized. At the other end, though, a player loses all manner of personalized roleplaying connections, from family and romantic entanglements to social ties and aspirations. It's about as satisfying as watching a really good TV show get canceled into its first season when it had enough plotlines for five. Most people probably fall somewhere in between, and it's hard to say where the majority is, but I'd guess the group who cares about a specific character as a persona is not a scant minority.
What get ditched are consequences with which one might actually have to deal. The 'encounter' gets turned into an isolated game. Alignment is essentially moot, and relationships with NPCs -- henchmen, hirelings, followers and subjects -- have been ripped out. Decisions matter less and less in everything from what happens in the imagined world, to how rapidly characters gain levels. What choices get offered are by design often -- and increasingly, in the shift from 3e to 4e -- trivial.
Again, vastly depends on the group. I find that there's been a steady increase in relationships with NPCs in most of the D&D games I've seen, starting right around 2e. The difference is that you spend more time relating to peers than vassals. While that may subtract a bit from the idea that the PCs are very special, given that there are other characters of their level as they ascend, on the other hand it makes certain roleplaying goals like romantic interests more satisfying. A player frequently is more interested in winning the heart of an NPC who is her equal than in obtaining the devotion of a hireling. Alignment is frequently moot, yes: but that's an outright feature rather than a bug to many groups out there. Villains become harder to spot and more complex. Player characters are defined by "what I would do" rather than "what a lawful good character would do."
I don't find that the replacement of certain sticks with certain carrots makes for worse roleplaying or more shallow character development. I think it simply makes another game option, one in which certain roleplayers prosper more even as other roleplayers don't.
The very basic concept that it's a game is undermined at every turn.
I don't agree. I think it becomes much less of a competitive game, and there's certainly not much D&D-as-"sport" element to it, but it's very much still a game.
Might it someday occur to the "New & Improved" crowd that this truism goes both ways? What is not going both ways is the carrying out of programs to replace "inferior" forms of fun (e.g., D&D, WHFRP) with what a faction of people -- who have not wanted for other games, more to their tastes -- happens to prefer. So be it, but can we at least keep the rationale real? The existence of "old school" D&D (or WHFRP, or whatever is next to the scaffold) was no oppressive force preventing people who preferred Ars Magica, Champions, Rifts, Shadowrun, World of Darkness, or whatever, from playing their games!
The existence of 4e is not an oppressive force preventing people who prefer older editions or new Old School Revolution from playing their games, either. It's basically another game option, and I think that's great!
When you have fewer RPGs on the market, frequently you would run into the issue that although everyone was technically playing D&D, they could be dramatically different styles. So someone who's always played hardcore Gygaxian D&D might join a group that started in the late 80s, was inspired by recent fantasy fiction, and basically threw out a lot of the consequences anyway as irrelevant to the kind of D&D they wanted to play. That player would be miserably unhappy (unless he found that the new group was a lot of fun, just different). Similarly, a new player who was more interested in long-term character development might be killed out of a more hardcore D&D game early, and decide that gaming wasn't really her cup of tea when the truth was that this particular style of play wasn't her cup of tea.
This may be something others disagree with, but I happen to feel that new editions don't themselves splinter the D&D fanbase: I think every notable shift is a sign that the fanbase was already splintered stylistically, and it's another faction's turn to write the D&D that in some ways they've always been playing. Now there are more games for everyone to play as written instead of trying to make a game system designed for someone else's style of play fit. This is a cool thing.