There are contradictory data on the question of whether HIV infection has a negative effect on the course of covid-19 disease. In people with well-treated HIV infection, there seems to be no difference, or at least not much, compared to HIV-negative people.
However, people with HIV often have additional risk factors, for example diabetes mellitus, cardiovascular disease or kidney disease. Then - as with HIV-negative people with such risk factors - the risk of a severe course would be increased.
The risk is also likely to be increased with low helper cell counts, for example in undiagnosed and advanced HIV infection, as well as in other people with severely weakened immune systems.