If you think a C172 has a huge markup take a look at the list price of an F35.
Normally big manufacturers end up pricing themselves out of the market when fresh competition is allowed to prosper - but in today's world this aint happening because of over regulation and litigation which feeds a lot of non-flyers.
The C172 will probably be in production for another 60 years and by then will cost as much as an F35 costs now.
The alternate pathway to getting into owner/flying is to buy a Fokker Dr.1 kit from the kiwis for $10k, source an aero engine ~$20-50K, and build it yourself.