https://musicbrainz.org/doc/Style/Release#When_to_add_just_one_release doesn't refer to barcodes at all, despite the biggest record company (Universal Music Group) assigning different barcodes to releases on the basis of bits per sample (i.e., 16bit normal vs 24bit hi-res).

As seen in https://community.metabrainz.org/t/digital-release-disambiguation/764780/1 this causes people to completely ignore barcodes when they see anything related to bits per sample.  For some reason, people also think disambiguation comments are unnecessary despite all properties of the release being identical outside of the barcode (e.g., same release date, same release country, same track count, same label).

One way to mitigate this would be to use better wording and bolding.

Before:

don't create a new release when the only differences appear in the following list:

...

After:

don't create a new release when the only difference is one or more of the following criteria:

...

Keep in mind that record labels may assign unique barcodes on the basis of these criteria.  If so, these releases should be separated in MusicBrainz with a disambiguation comment if applicable.