Traduction :He loves himself.
Accepteriez-vous :"he likes himself" ?
... il ne s'adore pas... il s'aime bien, tout simplement...
Je suis d'accord avec toi ! Pour moi love est pas utilisable dans ce contexte
Je pense que Duo est trop sévère ici. A mon avis:
Il s'adore = he loves himself;
il s'aime = he likes himself / (he loves himself is correct but nobody will use it in that sens); Il s'aime bien = he likes himself;
il s'aime trop = he likes himself too much / he loves himself too much;
il se plaît = he likes himself / he is pleased with himself.
PLEASE NOTE: Duo is correctly trying to teach that the verb "aimer", when applied to people or animals means "to love," and to objects means "to like."