That off-beat bass in back to the 80's is pretty easy, likely made up of only 2 parts. It's got a sub portion made up of a simple saw wave, lowpass that whole sound at about 130 ish (mess around with this, could probably go a bit lower tbh). Second part sounds like a simple saw pluck, maybe 3-5 voice, some detune and spread followed up with some pretty heavy bitcrushing to give it that crunch.
Music is the drug bass, again saw wave for the sub, leave more of the highs for this sub though. The second part is 2 or 4 voices, probably a saw again, a touch of detune, and iunno probably a touch of tube distortion, or maybe foldback.
I've found that the less layers these types of basslines have, the better they sound. The key is to get really good cohesion between your kick and bass otherwise it just sounds like ass.
