yeah, even if you limit the convo to it being about blog era rappers. He wasnt the only one. Dom did it to as you pointed outTo add to this , it wasn't even for for him on this album because he had jasongs with westcoast jazz leanings way back on the Kendrick Lamar Ep and Overely Dedicated era. He wasn't even the only one from California with this style. either because Dom Kennedy did too.
plus even on his own team(TDE) he wasnt the only one doing this, as others did jazz tracks to
really the whole jazz presence can be summed up as just something TDE in general has always meddled in. as they have had this for a while.