The experience of reading science fiction from the 1960s and 1970s now is an exercise in calibration. You have to hold the period context in mind — what was assumed, what was radical, what was unremarkable — while reading with your current understanding. What looks sexist now was often progressive then. What looks dated was often prescient. The calibration is its own intellectual exercise.

The Dispossessed (1974) is a good example. Le Guin was writing a novel about anarchism and gender and the relationship between freedom and obligation. The gender analysis has developed considerably since then. The anarchism analysis still holds. The book is not the same book it was in 1974 and that's not a problem.

Reading older SF as historical artifact plus living text is different from reading contemporary SF as only living text. I find both valuable.