It is not simply insolvency, but both last minute schedule cuts and IRROPS which pose problems. Some or all of that may or may not be fixed by EC 261/200r or insurance, but it can be a slog. While not every carrier will rebook OA for a 1-2 hour delay, when the wait is 2-3 days, it is not much of a worry. With ULCC's on long-haul, this can be a real problem.
Presuming that one is budget-minded in the first instance, it is worth considering whether the cheapest ticket is always the least expensive journey.
Sitting in a hotel for 2-3 days and hoping that one will be reimbursed at some point and fretting about missed work back home is a consideration which goes well beyond insolvency.