I remember when rolling out Yandex.Music (a similar streaming service) in 2010 we had maybe a dozen developers rounding way up, a half dozen strong BizRel team, perhaps three DevOps and a few managers. Totalling around 30 people, though dozens more would do some things by the virtue of being integrated in much larger Yandex team. Obviously we had way fewer regions/catalogue/listeners/platforms, especially back then.