I'm thinking that vaxxed people who have never been infected are going to spread the virus more easily when they finally do become infected than previously infected non vaxxed people.
Did the previously exposed person end up in the ICU and die from the infection on the first infection? They definitely are not going to spread the virus as much as someone that has never been infected.
What exactly is your point of comparing someone never exposed to the virus to someone that has been previously exposed, assuming they didn't die or become so seriously ill the they don't go anywhere?
How about someone that has never been exposed and never been vaxxed that then is exposed?
Are you are trying to decide if you should hold COVID parties, where you have someone that is infected lick everyone that isn't? Then they will be less contagious if they recover than someone that was vaccinated?
What about someone that was vaxxed, exposed and didn't die compared to someone that wasn't vaxxed, exposed and didn't die? That's comparing apples to oranges.
Your question is comparing two groups entirely different groups. It doesn't have any meaning. There is no control variable, there are two. You've got vaxxed and not vaxxed, exposed and not exposed. That's four different groups and you are leaving out two. What about never vaxxed and never exposed along with vaxxed and exposed? The comparison doesn't provide any information.
Really, what is the point of the comparison? The vaccine is to reduce how sick you get. It's like being exposed except you don't die from being infected. It's a fake infection so your body is able to learn to produce antibodies against the virus without having to risk getting ill and dying. In some vaccines, it is the virus. It's a dead or inactivated virus. In other vaccines, it is just the pieces of the virus that the body needs to be exposed to so the immune system can learn to recognize it and produce antibodies.
No vaccine can prevent someone from initially becoming infected. Everyone, whether vaccinated, previously infected ( assuming they are still walking), or never exposed will initially have virus in their body on exposure.
I wouldn't say you were "thinking", not really. I'd say you are looking for a strawman argument. And that is actually being generous. That, at least, demonstrates some point to your "thinking". Otherwise, you're just randomly putting one and "A" together for no particular purpose. Why exactly would you come up with two groups that have no particular purpose for comparison then?
If are giving some thought to it and just happened to come up with, what in all appearance, is a strawman argument on a troll website, that is if you are earnestly giving thought to it and mistakenly presented a troll OP, I do apologize. But then, let that be a lesson learned. Learning isn't always pleasant.
Or you are just a AI bot. It's something a AI bot would come up with.