(It's similar to my reaction to Lapis imprisoning Jasper, except we saw Lapis' unhappiness with Homeworld not only in "Jail Break" but in "The Return" and possibly also "The Message," I can't remember exactly what she said about Homeworld in that one and I'm too tired to look it up.)
Also, re: speculation on yesterday's post: if Yellow Diamond is a fusion, she's as good as Garnet or better, because we got a full-length view and she has no extra limbs—she might be hiding an eye under that hat, or maybe fusing with no extra bits might be a qualification for being a Diamond. I really like the idea that Diamonds are so giant because they're fusions and that Rose Quartz was one of the Gems making up Rose Diamond, but it seems less slam-dunk now.
("Not all Pearls know each other", hah.)
However, the summary of tomorrow's episode is "Steven sneaks a listen to a friend’s audio diary," so perhaps we'll get some more context about Peridot's thinking to make this work better for me.