Ok, i just read into the documentation a bit more and cxx_std_98 doest mean it will add the -std=c++98 flag, it simply means that it will require that the compiler AT LEAST support that standard. Here is some more info from the docs:
So im curious then, what would be the way in modern cmake to specifically specify u want the flag -std=c++98? I guess if cmake has a way to specify compiler flags u could use that method. Probabaly as i work through the tutorial, this question will be answered.