Why did Captain America grow old in endgame?

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Tags

1. #couldn
2. #branched
3. #theory
4. #because
5. #cinematic
6. #universe
7. #instead
8. #captain
9. #created
10. #travel
11. #endgame
12. #decades
13. #doing
14. #change
15. #established
16. #marvel
17. #earlier
18. #reality
19. #would
20. #impossible
21. #confirmed
22. #holds
23. #america