I don't know why Denis Arndt left, but it did strike me that what made his performance in Heisenberg so powerful was how grounded and lived in it felt, and I'm not sure given what was written and how Straight White Men was written that could have been possible here.
I saw Straight White Men yesterday and was really frustrated by how interchangeable, and unconvincing the characters were as people. When they weren't talking about white male privilege, which especially in the beginning of the play there was no realistic reason to come up (the world would probably be a better place if straight white males talked this much about their privilege unprompted, but come on), the sons were all immature rough housing nine years old, instead of middle aged men. I'm not saying middle aged men can't act immature, but for instance, the character of Jake had two kids and at no point, did the kids grandfather or uncles express any interest in talking about them... other when Drew points out Jake is a hypocrite because he wouldn't be okay if his kids grew up to be 'losers'.
Young Jean Lee clearly had things she wanted to say about white male identity and privilege, which is great, but I didn't think she was particularly successful engaging that conversation from the straight white male perspective. For instance, I've read some interviews with her about the play, and among the challenges she faced was trying to write a play about what straight white males talk about when they're alone even though she's never witnessed that, writing about sibling when she's an only child, and this being her first time writing in a three act structure.
To work around this issue, she had the original actors improv stuff, to understand how straight white males talk and think and incorporating that into the script. While this approach might have yielded such insights as men would rather be cold in a room than go put on a sweater, it appears there were blindspots in identifying stuff all people would do, such as a grandparent expressing interest in their grandchildren.
I think the central problem in this crowdsourcing method of researching the play is the character of Matt; who's the unintentional antagonist of the play, by not showing ambition and by possibly being depressed. Young Jean Lee created the character by asking a bunch of people who weren't straight white men what they'd like a straight white man to be like, and that became Matt. But she eventually had to take out an explanation for why Matt was acting the way he was because any explanation just made the audience hate him. Now I don't know what the thrown out explanation/s were, but it would appear to me Young Jean Lee wrote an entire play around a conflict, she could never find a realistic motivation for.