Parrot did burn through quite a few pumpkings. I wouldn't call them clowns either, but I do think they led Parrot astray. Obviously Parrot is not Perl 6, but they are closely linked in many people's minds for obvious reasons.
(It's not all the pumpkings' fault, either. I think Parrot would still have been doomed if its leadership were constantly flawless, just because it was designed before Perl 6's object system was.)
I would say that this hasn't been the case for the past 10 years at least. Patrick Michaud has been Perl 6 pumpking since then, to make room for Jonathan Worthington about 2 years ago. Hardly a revolving door and hardly clowns.