I let my 4 year old have tablet time and he'll watch a lot of YouTube and sometimes this stuff comes up (autoplay). If he started imitating some of the stuff or watched only that stuff I might be more concerned. We're parents that are involved and quick to curb any bad behavior though so I could see how it could be bad. The really cool part of it is he'll get a lot of ideas of how to play with toys then add stuff of his own and add his own stuff.
Honestly kids stuff in general can be messed up. Thinking back I watched a lot of messed up stuff:
-Tom&jerry and wile e coyote is like torture porn
-Pepe Le pew is a stalker that harasses women
-Thundercats...Semi nude half beast half man ... Basically the beginnings of furry culture
I wonder what kind of sub-culture these poop-eating, syringe throwing, costume wearing videos are going to create in the coming year.