The argument: most terrorists are Muslims, and Muslims approve of terror significantly more than other groups.

your responses:
-white people, gun owners, Christians, other privileged groups aren't blamed for the actions of "lone wolves", so it's unfair to blame Islam.
False. McVeigh was blamed on the right generally. Claims that McVeigh was "far right" bleed into claims that all Right is Far Right. Claims are frequently made that we live in a "white supremacist" culture, particularly after violence committed by police or white perpetrators against black victims, even single victims. Blame toward all gun owners is ubiquitous after every mass shooting, including the Islamic ones. Meanwhile, most terrorists are Muslims, and Muslims approve of terror significantly more than other groups. Argument not addressed.

-very few Muslims are terrorists.
True, but very few of anyone are terrorists, because terrorists are rare. most terrorists are Muslims, and Muslims approve of terror significantly more than other groups. Argument not addressed.

-managers commit the most theft via wage theft, most managers are white. Double standard.
There is no evidence that white managers steal more than managers of other ethnicities. If there were evidence that this was the case, that would be an argument for not making white people managers. There is evidence that most terrorists are Muslim, and that Muslims approve of terror significantly more than other groups. Argument not addressed.

-Islam is not a unitary belief system, any more than "white" is.
"Whiteness" has no unifying goal for its members to pursue. Islam is far closer to a unitary system than "white" is, being a coherent ideology built around obeying the Word of God as conveyed to his Prophet. most terrorists are Muslims, and Muslims approve of terror significantly more than other groups, "unitary belief systems" or not. Argument not addressed.

-Violent Muslims don't represent real Islam.
There's enough "fake islam" to provide a sizable majority of the world's terrorists, and a sizable minority of the world's muslims support terror. Argument not addressed.

-Muslims who approve of ISIS aren't aware of their crimes.
This actually does address the argument! Unfortunately ISIS' crimes are one of the most well-publicized news events of the last decade, so this is profoundly implausible.

-Pointing out that Muslims are violent will alienate them further.
People who get more violent when you point out how violent they are aren't people you want more of in your society. The Right gets accused of being violent and awful and deserving of destruction all the time. We suck it up. They can too. If they can't, all the more reason to keep them far away. Meanwhile, they actually are violent, as they provide the majority of terrorists and attacks, and approve of terror more than other groups.