If you have a harsh reaction to the AZ vaccine (an attenuated/weakened form) then it’s likely you would have had a much more harsh reaction to the unattenuated real virus.
I don’t think it’s been studied so its just a personal theory (ie read this as if it might be nonsense) but i suspect the people with bad reactions to the vaccine are also likely to be the people who would have had a more serious case of the real virus.
Don't use "it's likely" if you don't know what you're talking about, please. I appreciate you're qualifying your statement in the second paragraph, but please don't get in the habit of it regardless.
Side effects from the vaccines have a different cause and mechanism to most of COVID's symptoms. When people say they're out of it due to a vaccine, it's usually because of the fever that comes from the immune system kicking into gear. While COVID usually does cause a fever, its more dangerous aspects are from other reactions to the virus itself.
I don’t think it’s been studied so its just a personal theory (ie read this as if it might be nonsense) but i suspect the people with bad reactions to the vaccine are also likely to be the people who would have had a more serious case of the real virus.