edit: I think Kat said what she did because Phil continually embarrasses himself every time he's on a (usually public) call, plus she's probably tired. I can only imagine she's just sick of watching him step on rakes socially. Also, she seems like a very jealous person, and Phil puts himself in situations where he mentions other women because he's stupid, so every conversation is probably a bit of a minefield for someone as stupid as he is.
Speaking of jealousy, Kat only comes in/speaks up right when Wings starts talking about the female content creator Phil is accused of being one of the top donators for (although it was never confirmed to be him, could have been someone just using his name, but who knows). Early Bird is her name I believe. As soon as that topic comes up, Kat interrupts and shuts it down. Interesting timing.
I say Kat comes in/speaks up because it's very unclear. Phil claims at one point in the call that Kat is sleeping next to him and that she wears noise cancelling gear because the neighbors are so loud. But when we hear her voice, it sounds like it's clearly across the room, as though she's come to the doorway of the room Phil is in while chatting with Wings. Is Phil lying that she's asleep next to him? If she was, then why would she ask him to tell him when he's having these conversations since, presumably even with noise-cancelling headphones, you'd know if someone laying right next to you is having a conversation on the phone? To me it seems like he woke her up and she came from another room, but I'd prefer to believe that she was actually laying next to him for this whole conversation. The insane jealousy she has would explain why she spoke up and shut things down as soon as the female content creator Phil is (allegedly) a big fan of came up. But that's a stretch too because would she even hear Wings? It's all very weird.
Lots of other small interesting details throughout the call. Another thing is, if Kat is laying right next to him, it sounds very weird for Phil to talk about Kat and say "she's not even fat anymore". Even if I had lost a lot of weight, I'd feel weird hearing my partner talk about me like that to some 500 pound lolcow on the internet. It's just bizarre. Personally the highlight for me is when Phil pushes back against Wings calling their content "bubblegum content" that will get one view a year after it's done being streamed. Phil pushes back and says he still has people tell him, "and who knows if it's true," that they just checked out and loved his Heavy Rain playthrough. How does he still buy that meme? That's been a detractor dogwhistle for more than 5 years now, if not almost a decade.
To those saying it's possibly fake, I agree verification would be nice but this is no doubt real. The reason this livestream is unlisted/privated by Wings is that he was being trolled in Arc Raiders before this call, which is what prompted Phil to donate and ask to call in. People were following Wings around yelling nigger on voice chat, which is why the stream isn't up. Meerkat is a very trusted member of the dentractor community and I'm sure Wings will acknowledge this happened, and so Phil will be forced to acknowledge it as well. I wouldn't be surprised if he ignores it for a while though since it's so embarrassing. Also, I'm sure the chats or superchats can be verified somehow, but I'm so certain it's real I won't bother with it myself.