(Not the ladybugs or flowerbuds, but the other things, of course.)
They look despicable, but on the other hand they don’t seem actually to be doing anything. If they were some kind of larval form I would expect them to be actively chewing up the leaves, but they’re not; they’re just sitting there, apparently avoiding the sunlight. There’s another leaf just above this which I had to lift out of the way in order to shoot the photo.
Generally, there are a lot of ladybugs on the undersides of leaves, or on top of sheltered leaves, but there are more of these larvae or whatever they are.
Do I need to take steps?
I’m in Oregon if it matters, and I’m told the tree is a sedum, but I’m not sure that’s correct.
Make sure they stay in the trees and not around your house. There are safe-for-pets sprays you can get to spray your eaves and doorways to keep the earwigs under control.
No they’re not. They’re a mixed blessing; but they eat Colorado potato beetle larvae, which the native ladybugs don’t. And they do also eat the pests the native ones do; though they don’t stay active as long into the cold weather, so aren’t as useful about aphids on brussels sprouts.