You seem to imply every small non D&D game is doomed for failure (saying that 4e wouldn't have been as big as it was with having the name) when clearly that isn't true. Look at... well just about ANY D&D esque rpg, 13th age, Dungeon World, Mutants and Masterminds, Castles and Crusades... the list goes on. Most have been going strong (relatively speaking) for years now.
I guess another way of asking the poll is : Would 4e have survived if it was named anything else?
Just came to the thread and...deny the premise. Strongly deny the premise.
Your examples show why. 4E obviously outsold all those. Massively. But thats a fail for D&D and its owner.
So, if WotC had released and called it Encounter Master or something, sales would have been even smaller, and it would have been an even bigger failure.
If a 3rd party had released it...but how could they have? It was still expensive to make. But lets say they released the three core books of Encounter Master. Their immediate audience would have been much smaller, and all the more skeptical. If it was lucky it would have been another C&C or 13th age, etc. But so what? Another obscure fantasy heart breaker.
On top of that, the flaws of the initial release are worth repeating, as people seem to forget them over and over again.
TO START WITH
A VTT that was heavily, heavily hyped and did not work.
Gleemax (never forget).
Terrible, terrible positioning and initial marketing by WotC. This included...
Cancellation of Dungeon, Dragon and...
A very confused and alienating approach to licensing
An overwhelming release schedule that flooded the market with splat...even as
Adventure support was very week.
AND THEN
The game was filled with errors...
Monster Math,
A marginally useful DMG,
a PHB filled with dubious choices and weak builds for a game that was all about balance
HP inflation and over long fights
AND ALSO
The massive wave of errata that over reacted to those errors
The move to the online DDI
Essentials
THATS NOT EVEN CONSIDERING
Yes, all those things, like all sorts of world/cosmology changes, uniform power structure, magic items instead of gnomes in the PHB, ect, that pissed people off.
AND FINALLY
It can be pretty wonky, but overall 3E works fine at the level ranges most people play at.
WITH ALL THAT
I would consider 4E to be a great success.