Yes, most manufacturers will not honor warranty if you fire Wolf or any other steel case ammunition in your firearm. Same for reloaded ammunition whether personal or commercially remanufactured.
I prefer brass cased ammunition in all my firearms and refuse to put steel cased ammunition in any of my guns. You paid $800-1,000+ for the weapon and you're going to run the cheapest ammunition you can find through it? Doesn't make sense to me which is why I use quality brass cased ammunition. That being said, many AR owners shoot Wolf steel case ammunition in their guns without much issue.
Side note, Wolf is in Russia so good luck with customer service if something goes wrong.