It seems they have an international trademark on 'iracing.com'
Class 41: Education; providing of training; entertainment; sporting and cultural activities.
Cant see iracing.com wanting every iracingcountryname.com domain name. Their trademark includes an image so chances are its more the image that is trademarked. Just dont use a similar image to their trademark for your website!
Dont lose sleep over it and best not to worry until you need to lodge a response to official proceedings which will probably never happen. If it does repost. They dont own the world rights to the term "iracing" so dont worry