its not envy. its hatred for a minimalist musical artform where spittin' game is more important than lyrical ability (Jay-z vs. Nas), where 'beefin' with another rapper helps sell records rather than music selling records.
for the record, part of 50's sound comes from the natural lisp he has from getting shot in the jaw. that's why he raps about "being from NY but sounding southern". the 'dimples' in his cheek are exit wounds. if you listen to his pre-shooting tracks and his post-shooting tracks his voice is much more distinguished post-shooting.
so if you have a natural lisp and have the ability to double your vocals in a way that the 2nd take is close enough to the original to thicken it but not so close that it phases.
then do other takes where you purposely emphasize certain phrases.
now compress the double and emphasis tracks Motown style.
if you really want to sound special add delay (to your taste depending on the BPMs of the track) to the main vocal track, and add a touch of reverb to the heavily compressed doubled, emphasis, and ad-lib tracks.