IMHO there are a few things that need to be taken in consideration that are happening at the same time. The first is the fact that these subhumans are maniacs with a god complex whose only goal is domination over people. They relish it like noting else.

The second is the technological advancements that are happening together with the deployment of these "vaccines":

Elon Musk is putting tons of satellites in orbit for the integration of man and machine.

5G is being installed, which again facilitates this integration.

Bill Gates has patented a technology where some implant can mine cryptos while you are doing exactly what he decides you should be doing. That is the perfect slave tech: that 3 seconds you spent blowing your nose? UNPAID. Needs the above to be able to function.

The vaccine (obviously) which has an electromagnetic signature. May very well contain distributed nanocomputing clusters that feed on human energy and perform the functions listed above as Bill Gates' slave technology.

So that would make the vaccine their absolute key to total human enslavement.