As far as I understand, a bimbo is commonly a person that is superficial and put a lot of effort in an exaggeratedly hyperfeminine appearance, and people into bimbofication will sometimes want to be (or to look) dumbed-down to fit that persona, and I think this is what this post is referring to.
The difference between graveyard and exile in this context is that graveyard for non-creature spells is like a pile of old memories that you keep and can still access, while the exile is like becoming non-existent or out of reach.
Now that I look into it, though, I feel like the mill cards flavor is pretty fitting for the theme. Besides the mill and grind cards, it’s a lot of stuff that plays with your head, like “Mesmeric Orb”, “Mindcrank”, “Mindskinner”, “Fractured Sanity”, “Memory Erosion”, etc. While the cards that exile stuff from opponents libraries are less focused besides a few Faeries.