The problem with modern virology is two fold.
First - they are trying to sequence viruses without first isolating them. This is the core problem with HIV research. Simply put, they are chasing a statistical phantom. No virus has ever actually been identified and, further, HIV positive test results do not precioutate AIDS. Viral loading estimates with HIV are, also, a scam. The latest theories are that HIV doesn't actually shed, but instead inserts itself into the cellular lipids.
Why? Because, again, HIV has never been found in a cell and has never been shown to be destroying a cell.
What occurs in HIV positive patients with AIDS is that the immune cells bump into each other and treat each other as an invading cell, destroying each other and pulling more immune cells into the cascade.
This is why immune suppressants were partially effective at alleviating AIDS. They interrupted this cascade and prevented loss of immune cells.
But if you go back in time in HIV research, they would give HIV positive patients a "viral loading" - a supposed count of the amount of virus in their blood per unit volume. Which begs the question of how there can be viral loading measurements when the theory now states that there is almost not viral shedding/budding.
Smarter individuals wonder if the whole system got consumed trying to prove everything is an infectious disease that can be cured, and AIDS is a condition more nuanced.
The second problem modern virology has is that it is assumed it is abnormal for something to leave the body. IE - "asymptomatic viruses" - since the impetus for research is to treat an illness, almost all research has focused on illness and had avoided a more neutral research into the actual function of the human body. One who looks under a microscope knows that cells are always budding weird shit off and most of the things you see are a bit of a mystery - being part of a soup of biology in which the unknown outnunbers the known.