I haven't been able to figure out whether this question is on-topic, hopefully it is.
I have recently been wondering about how credits are given to the people who contributed to a song. To be more precise, on Spotify (probably not the best source I know), there are three main kinds of credit given for a song : Performance credits, Songwriting credits, and Production credits.
Judging by the names, one would assume that all the people who performed/wrote/produced the song would be accordingly credited as performer/writer/producer, right ? Except it doesn't appear to always be the case, as I will show with some examples below.
Take the track Teki by Alfa Mist : On Spotify, the writing, producing and performing credits are all given to Alfa Mist, but to me that seems obviously wrong, because Alfa is not the only performing musician on that track (all the musicians are listed on the YouTube link), so all the other musicians should be credited as performers as well.
Furthermore, Alfa is listed as the sole writer of this song on both Youtube and Spotify, but does it really mean that all of the parts were written by him ? Including the drums, the guitar solo, the lyrical part, everything ? Surely the other musicians had some say and influence on the final song, shouldn't they be credited for that ? (Maybe he's just that amazing and truly wrote everything, though that sounds crazy to me).
As another example, consider the tune Mirage by the great Art Blakey. Here again, on Spotify, the performing and songwriting credits are only given to Art Blakey. For the performing credits, that seems truly absurd, since Art is definitely not performing alone (musicians are listed on the YouTube link). As for the songwriting credits, it seems (to me) even harder to believe that Art Blakey, as a drummer, did write all the parts of the song, including the complex harmony and melody involved. Perhaps, here, "Art Blakey" should be understood as "Art Blakey and the Jazz Messengers" (his band) ?
All that considered, my question is the following : Is Spotify wrongfully/misleadingly attributing credit for songwriters/performers/producers ? Or is there something I am missing, such as maybe some artists willingly giving up their contribution credit through some preliminary agreement ?