I believe the point was that HIV alone does not motivate a bone marrow transplant. There are people with more urgent need for transplants and not enough donations to serve that need.

It goes without saying that it's unethical to motivate a bone marrow transplant for a person with HIV by giving them leukemia. I assume then that it was said either as a joke or just for the sake of completeness.

HIV is notable for its ability to create "hidden reservoirs". Some recent cure attempts have been aimed at intentionally "kicking" the hidden reservoirs in order to flush them out. For this reason I mentioned inducing leukemia as it would replicate the circumstances of the Berlin Patient.

For additional follow up, there have been additional bone marrow transplant attempts in somewhat similar circumstances with bone marrow that did not contain the mutation.

Further reading:

Hidden reservoirs: https://www.nature.com/news/hidden-hiv-reservoirs-exposed-by...

The "Boston Patients": https://www.nature.com/news/hopes-of-hiv-cure-in-boston-pati...

Yes. Though an allogeneic (from another person) bone marrow transplant is a high risk procedure. Some will say up to a 30% treatment related mortality.

You can cure Sickle cell disease as well with a transplant. Generally it isn't done because the risks are not worth curing a disease which has good treatment options (in HIV) or is generally a disease which can be symptomatically controlled in most patients.

That’s why the grandparent said “and/or” there, with a bit of humor attached I imagine.