Réponse :
X was not as creative as Y
X was less popular/famous/creative than Y
X was as artistic as Y
Explications :
il te suffit de rajouter l'ajectif entre as...as/ less....than
as...as= tout aussi exemple: X was as artistic as Y= X est tout aussi artistique que Y
less...than= moins que exemple:X was less popular than Y = X est moins populaire que Y