I would say over the last few years MSNBC & CNBC have become much less intertwined with NBC News than before. While reporters appear on both NBC & MSNBC, most MSNBC anchors now stay exclusively to MSNBC. NBC's Andrea Mitchell announced she will no longer host an hour on MSNBC a few weeks ago, the only other MSNBC anchor who also anchors on NBC is Jose Diaz-Balart. I guess you could include Willie Geist who does both Morning Joe & NBC's Sunday Today, but even then that's 2 anchors for the entire network that share an anchor role with both MSNBC & NBC News. I would say NBC News Now is already directly competing with MSNBC as opposed to acting as a companion. They don't cross promote each other or collaborate at all. I watch MSNBC quite often and they don't even acknowledge NBC News Now exists. When it's a slow news day MSNBC Reports will check in with someone from CNBC but there is zero synergy between MSNBC & the NBC News streaming channel. It's even rare when anything from NBC News gets mentioned. Before NBC News Now was launched, NBC would use MSNBC for special reports when breaking news happened at unexpected times, but even that rarely happens now. When it comes to splitting staff and covering events, I think it will be much less difficult to separate them now compared to 5 or 10 years ago. It's kind of like NBC & MSNBC already divorced but have continued living in the same house even after NBC has already moved on with NBC News Now.
As for why Bravo is staying, they probably feel losing the Bravo escapism dreck would harm Peacock, so they don't want to part with it.