You also have to remember that hindsight has proven it became very difficult to manufacture bicycles in the U.S. in a large-volume setting the way Schwinn did in the 1950s-60s. Schwinn's partnership with Giant showed that the Taiwanese company was situated better to produce reasonably priced, reasonably decent bicycles in the mass-produced range. Schwinn was stuck with an aging plant in Chicago. The traditional notion was that raw materials went into one side of a massive plant, and a bicycle came out at the other end. That style of manufacturing proved too expensive in the US by the 1980s, at least if you're looking at a mass-produced, low or mid level bicycle.
What I could see succeeding would be to try to negotiate a deal with a foreign supplier for the lower-end line up and then Schwinn's USA operation would scale back to making just higher-end bikes (something akin to what Trek was doing or what Waterford became). But even then, you have to give up on the notion that a large plant will be operating in the U.S., with raw materials coming in at one end and bicycles leaving the other by the thousands and thousands. And this had to be done years earlier - basically you need to think several moves on the board ahead, that you're going to give up on large-scale manufacturing of US-made Schwinns and convert the US operation over to premium bikes, while having a foreign supplier work the lower end of your product line up. Not easy stuff to predict, and certainly many other companies in the US got caught by the same trap in the 1970s-90s.
In a way, Schwinn is still operating in the US as Waterford today. And Waterford seems to have better grasped the US-made bicycle as a premium product for a higher-level consumer.