@icedquinn When looked at that way of paring down inputs, there's gotta be a sort of simplification of DAWs that almost replicates an old 1-4 track tape recorder but with the aesthetic sparseness in included instruments. Even programs like Audacity or OpenMPT go outside this boundary.
SuperCollider or CSound with a sequencer and Synth1 or 3xOSC, or GarageBand but all sounds played back are generated with FM presets or Additive synthesis. FL Studio but if it never expanded its feature set past 2004.