What part of board gamers do you not understand? Exactly one of those games has any serious adult players; the rest are for children or families with children.
It doesn't really matter if they're for kids. Very few popular and enduring tabletop games for kids or adults are rebuilt from scratch regularly.
<sarcasm>Because gamers (by which I assume you mean roleplayers) all have to learn D&D.</sarcasm> Frankly, I see a least one factor being a lack of interest in playing a six-hour multiplayer game, particularly where that six-hour is just one session.
The people I play with learn the new edition, usually to accommodate to what the group knows or what resources are most available, but they consider it to be a chore and need a push in that direction.
Then why would D&D be the game we're talking about here? Really old D&D stuff may have qualified as light-weight, but you pile up the AD&D 1 PHB, DMG and MM, and you've got a hefty pile right there, and it hasn't got better since then.
Okay, this is tricky but stick with me. A complex definitive D&D is fine, since most people are able to digest enough of one edition to functionally play. Most casual players can digest the core (not memorize it) and don't shut down when learning the rules. This seems to go smoother if it's the first edition they play - otherwise they may make some gripes about how things used to be.
For non-gamers complex rules are a deal-breaker, but for the casual crowd I think the combination of complex rules and planned obsolescence are the tipping point. Those gamers may shut down when they figure out all the rules they learned are antiquated and part of a cycle of planned obsolescence.
You've suggested nothing to fix that; you've said repeatedly that we'd continue to get splatbooks and all the expansions. Which means that a casual player will still have problems dropping into a big group, as they'll have the PHB and everyone else will be working from PHB, Complete *, Races of *, etc. (or PHB 1-20, or whatever.)
Casual players play with advanced players all the time and it's fine.
Regarding the image problem of shelves full of gaming material, it's the difference between
"My cousin has 30 D&D books but he says you only need to understand pieces of one book to play"
And
"
My cousin has 30 D&D books but he says you only need to understand pieces of one book to play. However all those books went out of date six years ago and now he has to buy new books because no one plays with the rules of those old books."
So it's better for the game to have an image of optional complexity than optional complexity and planned obsolescence.
And yet you don't play Call of Cthulhu, or RIFTS, or even GURPS.
Yeah, I don't know many people who play those games. I'll admit a lot of it is a product of brand loyalty and nostalgia.
Then why do you keep harping on one of the most complex games on the market?
Because my casual gaming friends and I like it? It's a good game. The complexity of all D&D versions is just right, it just becomes frustrating when it's endlessly rewritten and existing products. And we grew up with it and it's easier to talk them into D&D than most games I don't even know.
Most of those aren't indie RPGs. Some of those are among the most successful games on the market.
<sarcasm>Oh yes, Nobilis and The Mountain Witch, who hasn't played those? I'm sure all of my friends would jump right on the opportunity to play those games </sarcasm> Using sarcasm on a forum makes me feel dirty
So they have lots of time, but not enough time to get some familiarity with the new rules? Then why don't you play 2E or 3.0; even if you tossed all your old books, they're not that expensive to buy again.
Because some know 2E better, some 3.0, and I'm most versed in Castles and Crusades and 4E now. I wish we didn't have to reconcile those. I don't really like switching editions to accommodate what other people know.
And again, if you want to introduce them to something simple and stable, why choose D&D in the first place?
Um, well, because I'm sort of attached to it. D&D can be simple and should be stable. I want to play the edition I grew up with and have that shared experience with other gamers. <Sarcasm>
I'm sure I'm the only person that feels that way even though it's totally stupid </Sarcasm>. (Can we agree not to do that? It's pretty condescending and makes me feel like a really awful stereotype)
Anyway, it's about shared experiences and a shared core. If there was an edition that wasn't built on planned obsolescence, and it's not my edition that becomes the core, then at least we could move towards a core book at the center of the hobby that grows with us and unifies us. You know, with an iconic cover and art and a familiar table of contents where everyone at the table knows where to find everything. Lots of people have strong feelings about editions. But there's also lots of people that don't really care what vehicle gets them to where they're going, they just want to get there and make sure all their friends are comfortable while sharing the ride with them