It's a factor, but not the whole story. A lot of people are immunocompromised and for them just getting infected immediately raises the risks to unacceptable levels. We all owe the weaker people in our societies (from a health perspective) to take care of them, and if that requires us to get vaccinated to create a cordon of safety then so be it.
That there are a bunch of egoists that would rather have us all fend for ourselves doesn't change that, and usually those are exactly the people demanding we take on their burdens when the situation is reversed. It's called a social contract for a reason: taxes, vaccination against communicable diseases where possible, compulsory education and so on, it's the flipside of the coin, you get a lot of rights, but you also have some (sometimes moral) obligations.
That there are a bunch of egoists that would rather have us all fend for ourselves doesn't change that, and usually those are exactly the people demanding we take on their burdens when the situation is reversed. It's called a social contract for a reason: taxes, vaccination against communicable diseases where possible, compulsory education and so on, it's the flipside of the coin, you get a lot of rights, but you also have some (sometimes moral) obligations.