All the CMs for Apollo, as well as the space shuttles, basically used "Blunt body" technique for re-entry. While Apollo CMs used "ablative" type of heatshield, the space shuttles used "tiles" for the same. Which of the two is more cost efficient?
What is most cost effective depends on many things such as how well the technology is understood, how risk adverse the organisation using it is, how open to change they are and how important cost is when compared to other factors.
The Space shuttle tiles were a nightmare and each took multiple man days to fit and test and get right.
SpaceX also use tiles but are more focused on cost. The video link below says it all. It is true that the initial prototypes of Starship have (and will continue to) crash and burn, however I strongly suspect that they will figure out how to build a heat shield without spending man days to attach each tile.
Doing it the SpaceX way shows a great deal of promise for cost reduction and given their track record I would not bet against them. So SpaceX style tiles are probably the way to go for a cost effective solution (to be confirmed).