or whether the entire notion of a true Meritocracy is just a pipe dream that will inevitably be undone by greed, stupidity and envy?

That's the never ending cycle. Meritocracy is the basis for every progression in history.
Midwitocracy (a new word! - but I don't know how to 'tm' it..lol),

Midwitocracy then usurps the newly built structures (they are the natural bureaucrats, arse lickers..).
This then leads to atrophy and decay - and then the cycle starts all over again, through necessity.

It's cyclical, not linear - unfortunately.