Olympic sailing will never be a sideline, there will always be pro sailors taking it very seriously. What I am trying to consider, is how it will effect overall [rank and file] cat sailing across the board
Correct!... Fact of life... the Olympic sailors will not be competing in many regional regattas. they have no time.
So for a popular class like the Hobie 16... no spin! That means.. they show up for your NA's... When you have 60 to 70 boats on the line for NA's... do 2 Olympic team boats make a difference... IMO... No.
For a small performance class...eg the Tornado, does it make a difference... IMO Yes... you will never grow the class beyond the Olympic Sailors.
The problem with being the pinnacle of the sport... is that pinnacles are small... IF you have a large pyramid... to support the pinnacle.... great! If you have a narrow cylinder of a class... it is hard to grow this fleet.
I think that with mixed multihull... you take the Laser philosophy (Simple boat) and pick a Hobie 16 no chute.... You value popularity over performance.