My selfish reason was that having had pneumonia about 30 years previously I didn't fancy having a catheter (drain) in my chest for several weeks again. My selfish reason was that having had radio- chemo in the past I have a suppressed immune system, so flu or Covid could kill me. My selfish reason was that I wanted to continue living as opposed to possibly dying of an avoidable disease because I hadn't taken mitigating steps. So yes , selfish, in the same way that having a flu jab, or pneumonia jab, or an anti-tettanus jab or a malaria jab is.
But the plus side is that if you are vaccinated the risks of getting these diseases is reduced, as are the effects if you do get them - and that in turn brings advantages to the whole of society by, for example, reducing workplace absences (at least by duration), GP visits and hospital treatments - none of which are selfish reasons for habing a jab.
But if anyone is dumb enough to think that Covid is nothing more than a cold, maybe you should consider that colds don't kill millions these days. Or maybe it's just that nobody in your circle died of it