If the speakers are all working, with no defects, not sure it's worth touching.
However, the XO might be in need of an update. yes, caps can last decades, even out of spec can work almost perfectly. Just replaced the caps in my XO's, while my speakers sounded just fine, after swapping out the 10 caps (5x per speaker) WOW, like OMG WOW, sounds like a new set of speakers! Way more bass, way tighter bass, silky midrange, high top end. My tone controls needed to be reset, tweeter went from +3 to 0 bass went from +6 to +3.
It was the best $50 and 2hrs of work ever spent in my system.