It's not necessarily dead, but it's certainly bleeding players fast. If you look at the ELO leaderboards on guardian.gg for Clash (which includes last Iron Banner), only 963,500 players have placed on the leaderboards (25 or more games) for Playstation and Xbox combined since the April Update. While that of course doesn't represent all players since there are some who don't play Clash or didn't participate in the last IB, it's still a good representation of the majority of players since most do participate in IB. That number is a longshot away from the 25 million players Bungie was so proud of not so long ago (which we all knew was BS since they weren't all active players).