HIV integrase is used a lot in many gene therapies. It is very good at 'inserting a genetic payload' into a human's genome. So we often co-opt it to insert desirable sequences (see sickle-cell disease discussion ). Everyone's favorite Cas9 is able to cut DNA at particular sequences, but is not of much help actually getting a payload to load inline at the location that it homes in on. The HIV integrase is about the opposite, it's great at getting a payload to load inline, but it inserts relatively randomly (which is dangerous - an insertion at random spots could put code in the middle of an important oncogene). Ideally we'd have a kind of hybrid integrase/Cas9 that is able to both target, and insert a payload dna inline into the genome - at a specific site only.
The therapies described in the video are all small molecules. Some of the more interesting, newer therapies however are instead protein mimics that actually play a higher-level role in 'deceiving' rather that just trying to 'jam' the virus (see the eCD4-IG synthetic protein ).
Also, though it may seem obvious that having more tumor suppressor proteins like retinoblastoma protein , or Brca  or p53  should be a good thing, I don't think it is always so straightforward. On the other hand, elephants do have 20 copies of p53 - and they have way more cells than humans without getting a proportional amount of cancer.
Also if you think about 'where' you'd have to target the excess protein with the therapy it would be 'everywhere that might develop cancer', which is a much more difficult target than asking where to put the gene that encodes for hemoglobin.
tldr; we'll get there, but we're starting with more mechanistically determined/constrained problems before we move on to a cancer prophylactic.
This is in contrast to a videos like this one, where the molecules move with a purpose:
or this one, where you watch protein helixes magically self-assemble by zooming into exactly where they needed to be - a process so statistically unlikely it boggles the mind,
What's hard in these animations is to depict the mechanisms without using the motion-graphics equivalent of intentional stance ("x evolved for y"). Molecules don't have intentions, only electric fields (which are never shown) by which they move. That's not including quantum effects...anyway many molecular animations give the false impression that the molecules have agency.