According to https://wiki.musicbrainz.org/Style/Specific_types_of_releases/Soundtrack#Work the Soundtrack Work disambiguation guidelines date back to 2012 or earlier.  More recently, STYLE-193 created a dedicated "Soundtrack" type to contain all parts of a soundtrack in 2013.  I would argue this new Work Type eliminates the need to duplicate this information in the disambiguation.

For example, https://musicbrainz.org/work/55c16442-5fd1-3808-b13e-1e6cce3b1d78 has this relationship:

but it also has this disambiguation:

Are both really necessary?
1. The release relationship editor does not offer the ability to set the disambiguation comment when the Works that are the parts of a soundtrack would be batch-created. It seems like unnecessary duplication.
2. The "Final Fantasy VII" text can be automatically generated by the server using the https://musicbrainz.org/relationship/ca8d3642-ce5f-49f8-91f2-125d72524e6a relationship. Why force editors to store a 2nd copy of that data?