The point is that we won't all be immune because that never happens. If it did, there would never have been a need to invent vaccines. Diseases would have just died out after everyone caught them and natural selection would have applied and only the strong lived.
As has been shown by the recent outbreaks of measles and TB, to name just two, the moment the uptake of vaccines drop, the diseases come right back. Herd immunity only protects people if the majority of the herd have been vaccinated.
DD1 has multiple allergies and getting her vaccinated as a child was a nightmare. She was one of the first of the horrifically allergic generation and frankly, the doctors knew absolutely fuck-all about it. But I still had her vaccinated, as her immune system is really, really shit. Ironically, it was DD2 who contracted a mild dose of measles before her jabs were completed and believe me, she was horrendously ill with it.
Would I get the vaccine against CV-19? Quite probably. What I do know is that I am not in any of the groups who would get it first because of their health conditions. After that, once it becomes generally available? We'll all know a lot more about the virus by then, but it would appear - at the moment - to be very serious and as I get older, I can expect my immune system to be less effective than it is right now.
I think that anti-vaxxers will always be anti-vax, because they feel it makes them 'special' and 'unique' and so there is little point in talking to them as they are generally too stupid to actually listen and understand what you are saying to them.