Bonza was a 'luxury' - a leisure airline.
Rex is - somewhat incorrectly - regarded as an 'essential service' ... I totally beg to differ ... they're a business, that flies regional routes ... some being regulated / subsidised routes for two State Governments.
QF is the same.
Realistically, given the volume of routes that Rex fly competitively against other airlines, they should have done a deal with VA - that would have strengthened VAs credentials, built some scale for VA, and gone some way to re-establishing a nation-wide competitor to QF.
However - all of that - in hinesight, and given what had occured when AN collapsed - the then Federal Government should have gone out on a limb and done whatever they could to keep AN afloat (Tesna, VA merger, whatever) - we then wouldn't even be in this Rex conundrum.