Well, Alps switches are a lot less common nowadays. You've got mainly the Tactile Pro and the Solidtek KB-6600 and the related SIIG Minitouch, with a few Filcos here and there. Meanwhile, there's a ton of boards with Cherry MX. Back in the 80s and 90s, Cherries were a lot less common, while Alps dominated the mechanical front. Dell's AT101Ws, Apple's keyboards, Northgate, all sorts of third party boards, SMK, etc. all used Alps.