Maybe the next Mega Do will be a Kilo Do, with travel on an E175. That will preserve the exclusivity of these events as their appeal becomes more selective.
Seriously, it's odd that the Mega Do is having trouble drawing attendees when FT University and similar events are overflowing. It's almost as if the community of interest is changing from road warriors to credit card churners.

Probably, it's so easy to earn signup bonuses now. And manufactured spend heaven