So, we gonna talk about how this scene was pointless?
"I'll help you," she says, but it's clear Marinette had no idea what she was agreeing to since in the episode immediately following this, she seems completely clueless to everything despite Felix and Kagami literally spelling out, "GABRIEL AGRESTE IS MONARCH!" in bold letters:
And it's not like she could've been clueless, because she immediately pieces together the events she's being told:
They gave her this grand lore exposition, and in the next episode she's SURPRISED to find out Gabriel is the one she and Chat Noir have been fighting this whole time?
That brings the question on what did she even learn from that story? That Felix and Adrien were Sentimonsters? Did she just forget everything else?