The problem I have with your analysis is that I basically like 4e, and I don't see much of what I liked about it in 5e. So, for people who largely agree with you, and find 4e too "gamist" or whatever, it may be an improvement. But most of those folks are playing Pathfinder, and I don't know that they'll switch. For people like me, 5e doesn't seem all that compelling, and I'll probably either continue with 4e or switch to something closer to that.
As far as I understand it, the intention with 5E is to have a modular option that will allow 4E-style play but the reverse is not true (you can't play a simpler game with 4E without completely changing it).
Think of 3E and 4E as two very developed paths; 5E is meant to be a bit further back up the path, a simpler (more "classic") game that should, theoretically, allow for variants and options that are similar to both 3E and 4E. The problem with both 3E and 4E is that they're both to specific; they require too much buy-into their respective paradigms (detailed simulationism on one hand, gamism on the other).
As for whether Pathfinder players will try 5E, I think a chunk will.
This poll only has 65 participants so far, but its interesting to note that 46% (so far) are at least open to trying 5E.
But 4E and Pathfinder players aren't the only D&D players out there. They represent the bulk of
current players, but there are also a bunch of current players that play older (or retro) editions, and of course the untapped many that are either lapsed players or people who have never played.
As for lapsed players, let me say this: Don't underestimate the number of lapsed players who don't play not because they don't want to, but because they "don't have time to play that complex game" - which could apply to either 3E or 4E. Imagine that you haven't played in about 10 years, and the last time you played was 3.X. You were in your mid-20s and had the time to play. Now you're married, have a couple kids, and a busy career. You have some time, but can't see getting back into "that complex game." But out of nostalgia sake you check out the RPG section in Barnes & Noble and come across a shiny box set: "D&D, 40th Anniversary Edition - Play the game you grew up with! An all new, classic version, easy to start-up"...yada, yada.
You get the picture. Every new edition is an opportunity to re-capture old, lapsed players. This time around not only can WotC think about the people who haven't played in 20+ years, but those who haven't played in 3-10 years - lapsed 3E and 4E players who stopped for various reasons. A simpler, more classic game has a better chance of reeling them in then yet another complex game geared towards serious-to-diehard gamers.
