No woohoo Spooky Plate doesn't boost Dark-type moves what are you talking about. It's Dread plate fool! But yeah, Dread Plate > Black Sludge since Musharna's are idek. I'm actually indifferent about the Pokemon that moved up. I don't use them, they're pretty annoying at times, but really idc. My teams can handle them and I guess without Amoonguss we can only worry about the less-accurate Sleep Powder (which a lot of NU grass-types run iirc). NU gets Roselia and Stoutland, not quite sure about the latter but I guess TSpikes and Spikes will be more common now due to Roselia.
Also lmao Snover moved up.