So, I actually appreciated Jason's "so funny I forgot to laugh" comment because it showed some personality. All season I have struggled to get a read on him, and when he threw out that dated joke, I was finally like, "ohhhh, you're THAT guy." And then the scarf he is wearing in the scene-opening photo of him and Cassia made total sense.
Daya has the force of someone who is not going to take shit from anyone, but she just isn't that person... She's far more passive than she seems. I wanted her to confront Mama Brett when she overheard her talking to Brett, but she stayed in her room, just needing space from the situation. IIRC she didn't challenge Brett's racist BFF either at that awkward BBQ. Cassia, on the other hand, would likely have gone off on both women.
Also, Brett, I get that you need to work this out with your mom, but in addition to not having the conversation within earshot of your fiancée, maybe don't have it in the same room as your daughter, who is certainly old enough to understand.