Older Classes With Modern Rigs

Or maybe that's just your preferred style of boat?

I sailed an OK as a 'yoof' and thought it was a great boat back then (even with a wooden mast). Foam sandwich hulls and carbon fibre spars won't have done any harm to the performance and sailing manners so I'd think it's mostly because those old designs were well though out, conservative but not too conservative. Min weight for an OK is 72kg, same as the Blaze so no, not super light, but not a porker either.

Sales must be bad, Aero were only achieving 5 a week last year.

its a good point though that classes like the Finn and OK are just really nice boats made better by modern rigs. I do wonder if they would be made even nicer if they went further and used modern materials for the hulls too!

It's a balance. The OK isn't the lightest thing around, but it is tough as old boots and it's rare to see any breakages at all. The also last forever. You could no doubt make it half the weight, but would it make it a better boat? Possibly, but it would certainly make it more fragile and maybe reduce the competitive life. At the last worlds the 3rd place boat was a (very well sailed) 30yr old glass hull with a modern carbon rig, however most current boats are epoxy foam sandwich so fairly modern. The surprising new trend however is heading back to the dinghy boom with home built wooden boats, but this time built using laser cut kits that slot together in a jig and get epoxy filleted together. It's a good use of one of the best sustainable materials there is (wood) and again at the last worlds there were 2-3 home built boats in the top 10 so it's not a slow choice either.