If by "limits" people mean "safe boundaries," sure! If by "limits" people mean "someone to watch and care," absolutely! But what people usually mean by "limits" is parents who say "no / don't / stop / forget it / when you're older."
When unschoolers discuss limits they're often discussing arbitrary limits, trumped up to make the parents feel good, or used as magical talismans to guarantee that their children will be creative, healthy and safe. What creates much more magic is to help children discover and do and be.
photo by Sandra Dodd