Wow. What an unhelpful pi**ing contest this has turned out to be.
Some people observe that aviation part costs appear to be woefully inflated, and someone else points out that in some cases the costs of certification may account for some of the difference in price.
The latter side accepts that there may be examples of unwarranted padding of prices, and the former side accepts (without actually saying it) that there may be costs of certification.
I think we're done here ...., apart from Dunning-Kruger - Really ?