Its probably something to do with bringing in a covid-driven "two tier society" - the jabbed and the jabbed-nots. The latter of whom could then be excluded from certain activities (flying, going to sporting events, cinemas etc).
Possably I guess. But as far as I know this isn't a get two jabs and your done for the rest of your life situation it is to try and drop the spread and inpact at the moment, so will probably need a booster like the flu jab. I don't know if this will be given to everyone or only the vulnerable. There must be people who genuinly can't have the vacinne, so there must be a way that people who don't have it to be not excluded, if that is to show a negative test result for the antivax lot that is their choice. I have had the jab, but I also would defend the right of people to choose not to have it and they have, so I still don't get the logic behind it.