The current way in BIAB may be based on DOS, but how tracks are generated and how to make a RealTrack more versatile in a song project isn't dependent on the type of software the program was developed in. What matters are the tools, techniques and processes in the software used to make RealTracks more versatile. A visible waveform has no function or value in the generation of a RealTrack. It's a post generation editing feature.

The recent screenshot you posted would influence the quality of the track generation if the generation occurs in RealBand, the Stand Alone Plug-in, or the VST Plug-in compared to those RealTracks being generated in the main BIAB program using MultiStyles.

In my earlier post, in the attached images, that MultiStyle has 16 Substyles but only uses one of each a)-b) sub-styles of each main style. Simply clicking on every other Part Marker doubles the sub-style in that SGU from nine to seventeen. (end has a Part Marker)
The software being based on DOS is irrelevant to the audio produced.

Manually comping 25 bars of a single track with multiple instruments may be quick and easy in that simple demonstration posted, but manually comping multiple tracks and multiple instruments across multiple styles, it's a massive failure. Plus, in this screenshot attached to this post, The instruments and sub-styles were doubled in seconds which would further complicate manually attempting to reconstruct this MultiStyle demo in another program other than BIAB.

Attached Files (Click to download or enlarge) (Only available when you are logged in)
17 Sub-style Loaded Rather Than 9.jpg (187.6 KB, 54 downloads)
BIAB 2025:RB 2025, Latest builds: Dell Optiplex 7040 Desktop; Windows-10-64 bit, Intel Core i7-6700 3.4GHz CPU and 16 GB Ram Memory.