The most common complication would be food trapping. When the food gets built up, it can cause gum inflammation and tooth decay. It will cause more problems if the decay happens to affect other surrounding teeth.
Eventually, it can cause collateral damage as once there is a hole in your wisdom tooth, the hole will only get increasingly bigger.
Nothing is better than your own tooth. Fillings are not as good as your own tooth. But, it also depends on your oral hygiene. In fact, a bad filling can still do its job if you have perfect oral hygiene. However, perfect oral hygiene is impossible to achieve.