Mistsumi Cinch 28 way edge connectors Teac A-5300

These are the pretty bad quality edge connectors used in a lot of the old Teac stuff , they have been chopped  like every other one, I am not sure if thats because the pcb had two sides or its only a 14 way connector, you should clean these up with some contact cleaner. listed as sometimes you need to repace one as contact broke

What was Mistumi/Cinch thinking about here when they made these as could have done better.