With your logic, they should have cast someone other than Mark Hamill for the role of Luke in the sequels (and OT), as Luke is 53 in The Force Awakens, and Hamill is now 65. In ANH, Luke was 19, and Mark was 24, I think.
Same goes for Han. He was 63 in TFA, and Harrison is now 74, a few years after TFA. Bad casting. Who's the casting director of the sequels? Seriously. Oh.... Nina Gold. No wonder. Amateur.
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