Better a blaze of glory, I suppose.
In this hypothetical scenario, someone could have reasoned, hey, let's institute a backup plan: A. a way to investigate in-orbit for TPS damage; B. in the event of critical TPS damage, a way to get extra "expendables" (air, water, station-keeping propellant) to shuttle via unmanned backup system; C. a stopgap TPS patching solution; D. a backup way to get the crew home.
Yes, I know that the engineering challenges would be steep. However, few will dispute that NASA employs some really bright people. Instead of hobbling them with regulations and restrictions, what if some one had turned loose a mitigation "tiger team" of 50-200 really smart "rocket scientists" and engineers? I would be willing to venture that during 5 years such a team could have come up with a backup plan that would have some non-zero probability of success.
That NASA knew the foam was shedding, and damaging TPS tiles, has been documented elsewhere. That NASA knew that the loss of a single critical tile could result in burnthrough, and mission loss, is documented elsewhere. That NASA had no backup plan, no mitigation, is documented elsewhere (they stated this openly on the day of the disaster). This is profundly sad. I doubt very much that the NASA of Werner von Braun's time would have had no solutions to offer.