Hmmm, after 25 years of research it's back to square one.

"UCI biologist Dominik Wodarz has shown for the first time that the
development of AIDS might require HIV to evolve within a patient into
a state where it spreads less efficiently from cell to cell. This
counters the current belief that AIDS develops when the virus evolves
over time to spread more efficiently within a patient, ultimately
leading to the collapse of the immune system."

So, HIV progresses to AIDS when it has developed into "a state where
it spreads less efficiently from cell to cell."

It looks like the experts are STILL trying to explain why their deadly
virus doesn't actually kill anyone.

If HIV is at its deadliest when it's at its most inefficient, doesn't
that mean all HIV drugs should immediately be flushed down the toilet?

Presumably this is an attempt to explain away the fact that patients
who die from AIDS don't have a huge amount of HIV viral load sloshing
around inside them.