I would be inclined to go along with this. What is (and what is not) offensive is down to a matter of opinion. As capable and understanding people we can always decide what we might or not be offended by but we cannot apply our personal barometer to the one that is making statements and claims.
If someone wants to use the Ignore button on another member for the sake of them using an
offensive account name then that is their prerogative but it does not necessarily automatically mean some/all of their their posts will be low quality or even spam. Each member has to navigate their way around this I suppose.
What is offensive to you may be normal to someone else. Who decides whether it's offensive or not? If we ban everything that is "offensive to some people" as you say, I'm sure there will be very little left on the forum. Instead of wasting time on this, you can Ignore usernames you don't like.