Why doesn't HIV give you cancer if retroviral gene therapy gives you cancer?

Question

More than twenty patients have been treated in France and Britain, with a high rate of immune system reconstitution observed. Similar trials were restricted or halted in the US when leukemia was reported in patients treated in the French X-SCID gene therapy trial.[2] To date, four children in the French trial and one in the British trial have developed leukemia as a result of insertional mutagenesis by the retroviral vector. https://en.wikipedia.org/wiki/Vectors_in_gene_therapy#Retroviruses

HIV doesn’t seem to cause cancer directly, but over time it causes the immune system to become weaker, putting people living with HIV (PLWH) at an increased risk of many types of cancer. https://www.cancer.org/healthy/cancer-causes/infectious-agents/hiv-infection-aids/hiv-aids-and-cancer.html

Answer 1

Short answer: Most HIV-infected cells will die before transforming into cancer.

Retroviral gene therapy may increase risk of cancer since the integration into the cell's genome can be faulty (strand breaks, insertion into genes, cell stress and innate immune response, etc. ). Infected cells survive but might transform into cancer later in very rare cases.

HIV also causes integration into the host cell genome, probably causing errors, too. But most infected cells will die (apoptosis, overproducing viruses) before transforming into cancer. But as you said, the lack of an immune system increases risk of developing cancer in non-infected tissues.