I don't think the number on his back matters that much as I think I've said before. If you came back from the future and said he proved to be a better 7 for us than Mitch Pearce was, I wouldn't fall off my chair. Like if we picked Sandon 6, Brown 7 vs Sandon 7 Brown 6, I don't care, I doubt it would change how they play overmuch.
But one thing we learned with Pearce and reacted to way too slowly is that there's a kind of 6 he pairs best with. James Maloney, Blake Green, I would hypothesise Kieran Foran. He was never anything like as effective playing with an out-and-out running half or utility at 6. He literally played better with Jack Cogger than he did with Connor or Kurt. If we had Jamal Fogarty instead of Pearce I can imagine him combining better with the likes of Kurt Mann at 6, Connor Watson. Even though Pearce was a better overall player than Jamal.
I'm not ruling out that Brown can do what Moses did because yeah a lot of modern players are "halves" rather than specifically a 6 or a 7. A lot of good duos are two guys who blur the line between 6 and 7 rather than a traditional 6 and 7. But also, even with all our improvements in coaching, how physically demanding the modern game is, etc, these guys who are relatively small and schlubby and not even that talented, like Blake Green, Chad Townsend, Jamal Fogarty, Toby Sexton etc etc etc end up carving out long careers anyway. Because the stuff you want your half to do can be demanding in these very specific ways that you can't necessarily make up for just by being a really good athlete.
I would be very, very surprised if Brown's road to being recognised as a very good 7 involves playing with an out-and-out running 6 or utility.