Engineers and designers need something to do, so under the guise of "improvements" they design and produce all kinds of new things, most of which do not matter to most recreational riders. I consider myself an avid cyclists who rides frequently and who owns a few modern bicycles which feature most of the new designs (carbon fiber frames, internal cable routing, disc brakes, tubeless tires, to name just a few). All these improvements came with the bikes and I had little say in what they were. I was fine with bikes that were built forty years ago as I am fine with the ones that are built today. Manufacturers produce new designs to get cyclists to feel that what they own is not as good as what they could own. If you are not a professional cyclist you are a recreational one, and as one probably do not need the latest designs however much they represent improvement. I've always enjoyed the bikes I've owned, and if I buy anymore new ones, I'll enjoy them too.

I find it difficult to believe that an oval seat post has any measurable advantage over a round one in terms of speed or saved power.