I think per the style guidelines the edit is correct—but this strikes me (now) as a good reason to change the guidelines. I know when trying to find albums in the database it's very helpful to be able to search by a less-common artist; and indeed a lot of places your only choices are release title and artist. Sometimes only one or the other, like on the lookup/attach CD discid page. So I think in voting for that edit I made the database harder to maintain in the future, and that makes me think it's not the right approach.
Some of this of course could be handled by more fields, or flags on the existing ones. We could have a flag on each artist on the release if it's in big text or not. We could add a field for artists (and title!) on the spine. Of course, it'll make it take even longer to enter a classical release. And of course some of the search limitations could be solved by site coding.
But lacking more fields and checkboxes; and lacking search improvements., it seems like we should change the guideline to be simply: list all the artists on the front cover, composers first, semicolon, then performers. If some are indicated as more important, list them first in their group. This would let folks who need shorter strings for names do a simple truncate, and would preserve full searchability.
I see disambiguation strings (at least for releases) as mainly a last resort when nothing else can be used to disambiguate. The label kept the same catalog number, bar code, etc., but changed the cover art a little, or fixed a typo. Or released two slightly different versions to different retail channels. All kinds of minor differences which are beyond what we can reasonably build a schema around.
Their big problem is that they are free-form text. It's perfectly valid to have a disambiguation comment that says "blue cover", "'Agnus' spelled wrong", "Walmart exclusive version", or whatever. Trying to do anything with them computationally goes from a trivial MBID or string compare to an AI problem. Disambiguation comments are great to show to a human to pick from a few releases, but they're terrible for anything else.