Yeah because R9 didn't play for PSV, Inter, Barcelona, Real Madrid and AC Milan, yet only won 1 league title and 0 CL titles. He already played for top clubs. Neymar had a far better club career.
Yes R9 won the world cup in 2002 and was the top scorer in WC history for a while, but lets not pretend that 2002 Brazil wasn't packed with insane talent, and if you replaced R9 with Neymar in that team they would have likely still won the WC.
R9 is massively over hyped, considering he barely won any significant trophies, yet Neymar gets slated by many for not achieving more than he should have.