Re: At the risk of attracting many downvotes..
Some people get no symptoms, some get the sniffles, some die. Why take the risk when the solution is there to greatly reduce your chances of serious illness.
As why you should get vaccinated even if you have already had the virus, you are boosting your immune system. Vaccines generally give a better immune response than natural infection anyway and it is looking like COVID immunity fades with time, so we will probably all need boosters at some point.
Getting vaccinated after being infected was good enough for the mis-informer in chief, even if he didn't exactly advertise the fact widely. Shame, as it might have helped persuade some of his more moronic followers.