his unreleased catalog alone is better than a lot of rappers careers

It might also be due to the fact that Pac was more sociopolitical both musically and outside of music than Biggie and rap fans seem to pay more attention to that nowadays.

Biggie's a GOAT but his music didn't really touch on cultural issues much. He did touch on his own mental health and upbringing but wasn't really rapping about the bigger picture of society all that much.

Even Biggie's deepest songs largely center around his own life while Pac on songs like Keep Ya Head Up, Brenda's Got A Baby, So Many Tears, Life Goes On, Changes, I Ain't Mad At Ya, White Man'z World etc. looks at the bigger picture even while reflecting on his own life.

Either way, both are GOAT's and whoever is better is subjective.

no he’s one of the most interesting tho