The Viscounts were operated by state owned BEA/BA and operated much as a public service.
State owned BEA, while not always successful, did its best to try and make a profit.
You keep banging on about this 375 airfare.
If you book in advance its a third of that. Booking on the day because your ferry isn't sailing is always going to result in a high fare.
This happens pretty much everywhere that provides the same kind of route and aircraft.
I did point out that the people suffering are those who cannot book in advance for whatever reason.
If you want make a valid point, tell me of a comparable operation that doesn't charge these fares?
If you want to make a valid point, tell me of a comparable operation that charges these fares for 45 minute flights and is happy to operate half full.