On streaming platforms like Spotify or Apple Music it’s common to see single-track “releases” in an artist discography when that artist has a track included on a big compilation album. These single-track releases often don’t have their own cover art and simply reuse the cover art of the compilation.
I suspect that this is a way to game the system on these streaming platforms to make sure users get alerted about the new release by the artist in question. Considering the frequency with which this happens I also suspect that it’s an automated process.
Should these releases be entered as singles into Musicbrainz?
I personally wouldn’t add a new release for that Knowhow page (or other similar pages like this one for Battleground). The compilation allegedly came out first (not that I particularly trust data from streaming platforms), so it doesn’t feel to me like there was a distinct single release event that’s worth trying to capture.
This is just my opinion rather than a guideline that I’ve seen written down, but if someone couldn’t be bothered to create a unique cover image for a song that’s already available as part of an album, I wouldn’t create a release for it just because it happens to have its own page on a streaming service.
With that said, I also wouldn’t vote against someone’s edit to add it if they care enough to enter it. There unfortunately aren’t many guidelines about how digital releases should be entered (as evidenced by hundreds-of-messages-long threads discussing topics like release countries), so everyone’s just doing whatever seems right to them.
I’m not sure I understand, the cases I encountered this were labels that release primarily digitally (with some compilations never released on a physical medium at all). In all cases I found both the “single” and the full compilation are available on streaming services.