Travel insurance generally does not cover delays, those that do have limits in place, ie 6 hours plus before you get anything. The fine print across policies is generally heavier vs the airlines conditions of carriage.
I remember Tiger in its first few months when it started, tried that. Dumped all passengers on the Gold Coast, told them refunds will arrive in a few months and the Managing Director told the media ‘they should have purchased travel insurance’. It was all downhill after that.