If you take into account the society, the culture and the way of thinking of one certain period, then you can find any kind of historical character relevant for the 21th century. E.g. Jean Jacques Rousseau was a mysoginist but still he is one of the writers who inspires us the most due to his ideas and his "freedom" of spirit, seen from the lenses of the XVIII french society. If you take a historical character and you analyse it from the point of view of someone from this century, then you'll need to do a very hard job to find at least one character to be admired