Unless you're planning to isolate at home indefinitely or live somewhere very remote you are pretty much guaranteed to be exposed to covid at some point. A good proportion of my friends have already had it twice. Consider that Omicron is more infectious than the common cold and how many colds you've had in your life.

The main risk factor in whether you develop an auto-immune disorder (other than the specifics of your own body and immune system which you can't do much about) seems to be the severity of the infection. You can still get these issues with a mild infection, but it's much less likely. And a vaccine pretty much is just a very mild infection with an engineered variant that can't reproduce, which then also reduces the severity if you later catch it. So intuitively it would seem like a pretty good bet. And as others have pointed out the statistics support that this is also true in practice.