Isn't Wikipedia's Pizza Effect article therefore an example of the Pizza Effect?
You state surprise that it has existed so long, then go on to explain why it might have done, which seems to meet all the conditions you describe.
Namely it always existed in its place of origin (Wikipedia), but has improved in reputation through interest and prestige elsewhere, and is now better as a result (through people on Wikipedia improving the article)?
Isn't Wikipedia's Pizza Effect article therefore an example of the Pizza Effect?
You state surprise that it has existed so long, then go on to explain why it might have done, which seems to meet all the conditions you describe.
Namely it always existed in its place of origin (Wikipedia), but has improved in reputation through interest and prestige elsewhere, and is now better as a result (through people on Wikipedia improving the article)?