Being basically an anti-social sort, for me, the idea of a flotilla sort of defeats the purpose of going to sea, but I do understand that is not everybody's perspective.
One big downside I have observed with large flotillas with many inexperienced sailors is the "analysis paralysis" experienced when it comes time to pick a
weather window to leave. Yes, theoretically, every
skipper makes his own decision, but it is easy for the group to be swayed by the one or two most timid, indecisive and tentative boats in the fleet.
Invariably the perfect becomes the enemy of the good, and multiple good departure windows come and go because they are not everybody's idea of "perfect."
It might not be fair because I have had enough experience and
learning to have confidence in my choices, while someone new to the
game is looking for the wisdom of the crowd to help validate decisions. Unfortunately, what they all too often end up with is best described as the lowest common denominator.
I imagine that
new sailors picture this coordinated fleet of vessels moving in harmony across the sea within easy hailing distance of each other for a thousand miles or more. That is just not reality.
Boats very quickly disperse, scattered by different speeds, pointing ability, and sailing skills. Once they get a dozen miles apart, they start to experience different winds, and that spreads them even further. After 3 days you will be lucky to be within reliable
VHF range of any other boat. Crashing into your fellow flotilla members will not be a real world concern.