Regium spent a fair bit of money (10s of 1000s) in ads on chess.comm, chess24.com and at least one magazine (although some of the ads might not have required full up front payment) and the videos and website would have either cost money or time plus software.
chess.com had live ads read on streams by presenters, the presenters looked and sounded really sceptical it was legit, didn't stop them from taking the money and advertising it to their customers, though.