Gazza M Yes, though I honestly think it's less about sheer reputation or on-the-pitch quality and more about image rights, marketing, etc. Real Madrid make more revenue from kit sponsor and manufacturer than virtually any other club, and having figures like Vinicius is a vital part of their business model.
It's also why they will happily let him go if he asks for too much money, and why Arsenal probably did the right thing looking around for a possible deal. Ultimately it's Vinicius that's killing the transfer if he doesn't come, not Madrid.