a. Cats have very little to do with monos in this regard. They are skinnier and the rules are different. Obvious.
b. Cats are about functions, not mono hull
I don't believe anyone has mentioned what that big flare does if the bow burries at speed (boat stops, pitchpole is possible). Hobies were famous for both flare and pitchpoling. While some flare can provide work space and a drier ride, flare and overhang MUST be limited on any high speed multi.
You won't find flare on high performance one designs (mono or multi); there isn't a rule
to consider and seaworthiness is generally improving... at least for high speed sailing, which all cats should aspire to.
Yes, Warram got a way with it, but it was actually minimized in the Pahi
line for this reason. Also most of his boats are nothing like cruising cats (little cabin) and so close comparison is false comparison.
But folks cling to traditions. I think it is genetic.