I think you are misunderstanding how they work.
They do not stop you getting ill, they reduce the chances of you getting ill by a good margin, they reduce but not eliminate transmission. They stop you from dieing.
There will still be transmission of the virus, and the more elusive strains will still likely make you ill as the vaccine is not effective against these other strains. As soon as we allow people to go on holidays again more strains will enter the country that are likely to beat the vaccines.
Enjoy this upcoming break from it all, but we are not even half way through this yet...