Why is the new 50/1.4 three times more expensive than the old one?

headfirst wrote:

what new 35/1.4?

If you meant 50/1.4 then it's a 30 year newer design with R&D costs at 201x prices not 198x ones (in fact the development costs on the old one will have been recovered/written off years ago), it's SSM & yes, Zeiss licencing costs. & they won't be anticipating selling as many so R&D has to be recovered on a smaller no. of lenses.