That applies to warrants for arrest. The standard warrant ICE operate with is a civil warrant, and does not confer any actual authority to arrest an individual.
I keep hearing over and over the ICE warrants aren't real.
If they are arresting people using them and judges are recognizing them, they are real and the people demanding an arrest warrant are the sovereign citizen-tier people screaming at the sky wishing there was a different reality.
There are multiple types of warrants. All types are "real", but they convey different authority and different requirements upon both the arrestee and the arresters.
It is both rational and legal to insist that law enforcement stay within the bounds of the authority the specific type warrant they obtained. ICE civil warrants grant different authority than every-day federal arrest warrants. That ICE is abusing that authority is no reason to capitulate to it.
There are two different warrants. Ones issued by judges, which are "real" and ones signed by ICE supervisors which are little more than legal authorisation that this agent can go out and investigate a person -- even if they nevertheless attempt to arrest them.
That's a general applicable law that prevents anyone - judge or not - from interfering with an apprehension.