Both transcended their genres. Bob Marley had a much longer career but Tupac's catalog is more consistent. I would say the publishing value between their most universally recognized works is a toss-up, however if you go down through the tiers of their catalog's rankings Tupac's lower tier work is of higher value than Bob's. That's why you see throwaway tracks of Tupac's getting remixed for movies like Django . . But Bob Marley's low-tier work is almost like demo quality
Bob Marley's songs
"Could You Be Loved"
"Is This Love"
"Satisfy My Soul"
"Don't Worry About A Thing"
Those both universal and timeless
"One Love" can be put up head to head with "Changes" or even John Lennon's "Imagine" - I would actually say Tupac has more top-tier work but not as universal as those love themed songs mentioned above, so you'd see those placed in certain types of movies, action-dramas as opposed to romance-comedies or romance movies
When people say these things are a matter of opinion and are subjective in nature they are simply wrong. The value of a catalog is very quantifiable
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