The robot difficulty isn't the issue, like you said, it's that they don't stop, or even slow down even slightly with their spawning rate. Soon as you kill even 20 of them, they're back instantly before I can heal and reload. There is exactly ZERO reward for killing them. Kill one of them, they spawn back in one second, kill 30 of them, they all spawn back in one second. That makes no sense to me whatsoever. If it was a level in a zombie game, where it's supposed to feel impossible until you arm whatever, that could make sense. That's not what this feels like though, plus, you're not eased into it. This isn't some level towards the end of the game, it's a standalone mode. That's why I say Dice simply doesn't get it. This is fundamental design stuff I would think.
I think the friendly fire should have been saved for a harder difficulty or a particular challenge. It's strange they added that in for this mode. Between that and the robots never slowing down with their spawning is making this too difficult with randoms.
Overall, it's a very simple mode, with one enemy type, and one objective. So I guess I don't feel like I'm missing out on much. The skins do look really cool, and I think they should make a PvP mode based around that maybe. I'm not spending more on the game for them, but I do really want one lol.
I'm glad that I'm not the only one feeling this way about this new War Machine mode. I have at least 3k hours in Destiny 2, so I'm a fan of PvE stuff mixed in with PvP. It can be nice to have a break from other players once in a while, but this doesn't feel well crafted. I feel a bit bad about being a little harsh, but like can't Dice get better testers? Have actual people outside of their studio give this stuff a go? I always find a disconnect between people making games and the ones who play their game relentlessly. It's two different kinds of minds from my experience. Especially for shooters.