I wouldn't say it's "a good thing" but there are studies now coming to light which to show how vaccines can be responsible for auto-immune diseases. That's a long list of maladies. Been telling people who bragged to me about getting annual flu shots for more than twenty years that it could screw up their immune system. So, that's how long I've been a conspiracy theorist according to them
Oh well.
The studies are charting the situation and from what I see it appears that approximately 20% of people with three C-19 boosters are F'd. They call it
Grave's Disease . If you read that link you'll see that the cause is said to be unknown... Not so much anymore.