Businesses which rely on Facebook, as their sole distribution channel could get out of business if Facebook goes out. A lot of economical value will be lost.
Many of these businesses are small single-person operations with little tech understanding that are using, for example, FB marketplace. They wouldn't even know what you meant by "single point of failure."
Allowing copyrights to expire on pre-1950 creative works would also destroy billions of dollars of "economic value", but that doesn't mean it would be bad for humanity.
We should be careful to not take our values from a spreadsheet.