I think the $50,000 thing is a red herring. That was for five seats, of which four were functional. Totalling all of the ticket prices in one figure is the journalist's / headline writer's instinct to dramatize the situation. "$50,000 on airfare!! Can you imagine!! More than most people earn in a year!! And then he got stiffed by a broken seat!!"

The issue is that $10,000 worth of product was substituted for inferior product. If the exit row Y seat cost less than $9,500, I think the passenger deserves a larger credit.

The remedy that seems fair to me is a refund to the fare applicable to a non-lay-flat seat on the same aircraft.

We regularly read on FT a declaration of the prerogative to deboard if an aircraft substitution results in a non-lay-flat seat when the passenger chose the specific flight and fare class to get that seat in order to lay flat and sleep.

In this case, the substitution applied to just the one seat and was not intentional on the part of the airline, and the aircraft was already in the air when the substitution was discovered by the passenger. (It would be outrageous, but not beyond imagining, if Air Canada knew the seat was faulty and still allowed it to be occupied without disclosing its condition.)

Aside from the food and beverage service, which clearly does not account for the majority of the $10,000 value of the seat, the passenger got seating comparable to a bulkhead or exit row, but not lay-flat J, so that is the maximum he or she should pay for THAT seat. The other four seats got what was paid for, and although they likely have also suffered in the form of hearing the grievances of the fifth person, are not entitled to any compensation.