Of course it does. Promos help tell the story.
Look at Cesaro. Look at Bayley. Cesaro is over now, but he's nowhere as over as he used to be when he was part of the Real Americans. If he knew how to be a convincing actor and learned how to emote, he wouldn't be stuck in a tag team going nowhere with Sheamus.
Bayley has been saddled with shyt stories and she can't talk at all, and she went from being a potential female Cena to barely getting a reaction.
Promos don't matter? Tell that to Roman Reigns. The promos and stories they've given him have made him look super corny, and he's never recovered from 'suffering succotash'