The squabble over this becomes more interesting. Hollywood, and (worse yet) Europe v. "middle America" (whatever that may be).
30+ years on, it's difficult to even remember how this transpired. He apparently pled guilty in expectation of a particular plea bargain, and, when that did not pan out, left the country to avoid jail time. He apparently settled a civil suit brought by the victim.
One assumes he is guilty, and that he has escaped punishment for many, many years. It appears law enforcement could have picked him up long before this, so it's reasonable to wonder why it didn't do so, and why it's decided to do so now, particularly when the victim has made it clear she wants no part in the forthcoming circus.
It is silly to maintain he should not be punished, particularly for reasons based on the fact that he's an accomplished filmmaker with lots of famous friends. He should have been punished long ago. But it's not silly to wonder what will be accomplished by the ensuing expensive, time-and-resource-consuming mess, especially given the passage of time. Will wrongdoers be deterred as a result? Not likely. Less fortunate wrongdoers would have served their time by now, and very few, if any, will have the options, and be given the leeway, Polanski has had, in the future. Is this being done because law enforcement feels guilty for giving him a pass for three decades?