Racing has no bearing on the public? C'mon you're in the automotive industry. Of course it does. Granted it may take time and granted still, a very small population of bikes ever make it into UCI competition, but that does not discount the fact that bike manufacturers do design around UCI regs and this technology does eventually trickle down to the masses. When you look at all the "halo" bikes from the major manufacturers they are all designed to be able to enter UCI competitions.
This trickle down effect filters down to the amateur racers --> road bikes etc. Take for example, the (over)emphasis on weight. It's pretty well accepted that weight is not as important a factor as aerodynamics but cyclists are infatuated with the weight because this is what the UCI emphasizes (and yes, I know there are production bikes that weigh less than the UCI weight minimum). There have been lots of bike designs that incorporated fairings and aerodynamics, that IMO looked REALLY cool. Except it will never make it out of the concept stage because the ROI would make it impractical without race dollars, and they can't do that while trying to comply with UCI rules.
Probably one of my favorite examples is from Specialized's designer. A concept called the
fUCI
Now imagine something like that in a race. Fairings would get adopted almost overnight, trickling down the racing ranks and eventually onto a commuter.
Electric motors are STILL viewed as taboo by many cyclists. A small, "burst" type assist motor powered by an ultracapacitor would keep things relatively low weight and would add another dimension to a race would get cyclists. I mean it's not like they're not using this in competition already, lol.
With recumbents, I think the challenge there is that they don't resemble what most people think of as a bike and also presents some challenges that make it unsuitable for the masses, namely packaging (space) and low visibility.
I get it with the wanting to see the athlete perform not the tech but with the UCI that doesn't hold true either does it? I mean when a smarter racer (Graeme Obree) figured out that a nice compact tuck position was more aero and thus faster broke the speed record, they banned the position. The bike he did it on looked waaaaaay different from what was accepted as "racing" bike.