When two or more artists band together and create art, it is likely that they can be considered a corporate body and established in NAF according to RDA. If the group name seems to be the result of art historical research or art criticism, and the artists are not known to act collectively, the group might be more appropriate in SAF. In recent years, LC seems to be veering toward NAF for artist groups.
Art movements are also established in SAF. Some historical movements such as Dadaism may have produced manifestoes and other collective writings but a topical heading for the movement is used.
As in most cataloging, applying cataloger judgment is appropriate.
https://commons.wikimedia.org/wiki/Category:Dada_artists#/media/File:Dada_artists,_group_photograph,_Paris,_1920.jpg