Remove entries from finder's context menu?
You can actually remove native MacOS items from the context menu....but unfortunately, it doesn't appear you can remove the ones you indicated above. Regardless, if you want to take a look, head to 

System Prefs > Keyboard > Keyboard Shortcuts > Services

and then uncheck the items you don't want on the menu.



It's unfortunate that you can't remove all of them. But it can at least help you get rid of some of the clutter.