1st. Omicron makes easy work on infecting people with whatever 2-dose vaccine
2nd. For whatever 2-dose vaccine, while offering less protection on infection, they still provide a lot of protection on hospitalization/death (important for ending the pandemic)
3rd. Antibodies are not everything. The immune system also has T-cells
4th. You get "super" protection if you are vaccinated with whatever 2-dose vaccine and you still get infected. This should be enough to protect you for a long time
5th. Omicron is mild. If you are vaccinated with a 2-dose vaccine, there is huge chance you will just get some fever and a sore throat and then you will recover.
Omicron is a straight ticket towards completely opening up the world (for the West at least). I estimate that by February they will open up everything and stop bothering with it