One argument is that positive externalities, such as higher growth due to global mobility, outweigh the microeconomic losses and justify continuing government intervention. A historically high level of government intervention in the airline industry can be seen as part of a wider political consensus on strategic forms of transport, such as highways and railways, both of which receive public funding in most parts of the world. Although many countries continue to operate state-owned or parastatal airlines, many large airlines today are privately owned and are therefore governed by microeconomic principles to maximize shareholder profit.
You seem to have your heart set on Zakynthos but I have to say it’s not a good use of time for a sort-of overrated payoff. Your time is much better spent (in my opinion) seeing another Greek island in the cyclades (maybe taking a ferry to Naxos or Paros sitting outside on the deck drinking a bottle of wine) rather than taking a bus and connecting flights. Zakynthos and Santorini/Mykonos are on opposite sides of the country and the only way from one to the other is by flying (or some combination of bus and ferry). So, my recommendation is to consider spending those Zakynthos days in Naxos, Paros, Milos, or some other Cycladic island.
Ultimately, the federal government provided $4.6 billion in one-time, subject-to-income-tax cash payments to 427 U.S. air carriers, with no provision for repayment, essentially a gift from the taxpayers. (Passenger carriers operating scheduled service received approximately $4 billion, subject to tax.) In addition, the ATSB approved loan guarantees to six airlines totaling approximately $1.6 billion. Data from the U.S. Treasury Department show that the government recouped the $1.6 billion and a profit of $339 million from the fees, interest and purchase of discounted airline stock associated with loan guarantees.