PpS you are absolutely right when you say:

< I suspect most of these new builders are not going to make it >.

Only in the last few years I am aware of 3 well known catamaran builders which did not make through into the A class market:
a) both the Italian Mattia&Cecco (now MattiaSport) and the Swiss Ventilo had an A class design in their range of boats just for one year (perhaps they were able to sell 3-4 boats each);
b) the English Stealthmarine announced in 2004 the launch of a new A class cat fitted with a revolutionary canting rig; the result evidently came short of expectations since the info was cancelled from Stealthmarine's web site. I suspect that only the prototype was built.

Also the BIG players in the A class market, traditionally BIMARE and Boyer Fibrecraft, could not avoid to do (quite) BIG mistakes:
the production of the Bimare Javelin A and of the Boyer MkV was discontinued respectively after 2 and 3 years. However, thanks to their name and reputation, both boatyards could sell anyway quite a few of them.
Also the Flyer is going to undergo the same fate:
as anticipated Boyer Fibrecraft is developing a new Martin Fisher's project and Gel-Tech, (and supposedly Aicher & Egner for Europe), have started building the Flyer Mark 2, again a Peter Egner design, the second itineration of the most winning A class design in history.