The demise of TWA is often blamed on investor Carl Icahn who acquired the airline in 1988 through a leveraged buyout. But the reason it was an attractive buyout target even then was because its assets were of greater value than the airline.
The biggest strategic problem that TWA faced was St. Louis. While other airlines were making money in the late 90s, TWA wasn’t, and that was largely a function of their home market. St. Louis didn’t have nearly the percentage of high yield business passengers as other airline hub cities.