HIV has a very fragile envelope, which is formed out of the host cell's wall (a phospholipid bilayer). Also, the spike glycoproteins that mediate entry into new cells are themselves very fragile (a certain number of these come apart from HIV virions as they circulate, even with the full protection of the stable osmotic, pH and temperature conditions found in blood and lymph).
If these things are damaged (as they are when the virus is exposed to the atmosphere, or to enzymes in saliva), they're rendered non-infectious. So many details would have to change about the cells the virus targets, and the way that it enters them that I can't see how it would be the same virus, with the same pathogenic effect if it were somehow to become airborne. There are tradeoffs in everything, and viruses face them too.
Dont overstate this particular study, the team did nothing to eliminate the possibility that there was transmission via droplets flung off the animal, and did not fully eliminate the possibility of particulate cross contamination which could have lead to transmission via infectious fluids piggybacking to the macaques on the particulate cross contamination.
Yes there is a risk of mutation to transmit via air, but we have not yet seen it. We have merely proven that 'shit happens' and 'ebola is dangerous'.
Ebola kills 90% of its victims in a matter of weeks while the life expectancy for someone with HIV in the first world is almost the same as anyone else [1]
If these things are damaged (as they are when the virus is exposed to the atmosphere, or to enzymes in saliva), they're rendered non-infectious. So many details would have to change about the cells the virus targets, and the way that it enters them that I can't see how it would be the same virus, with the same pathogenic effect if it were somehow to become airborne. There are tradeoffs in everything, and viruses face them too.