The whole thing has become ridiculously complicated because Lucas basically changed his mind about Anakin’s age. Back in '83 Anakin was supposed to be an old man. Lucas even said “in his 60s” or something similar at the time. Assuming that Obi Wan and Owen were also supposed to be older than the prequels implied, this all made perfect sense and the appearance of Shaw at Ewok-fest was absolutely fine.
It was only when George suddenly decided ROTJ Anakin had to be in his mid-40s - and corrected it with the dumbest SE change since the Han debacle - did this become a canon issue.