HAHAHA Only an HN comment could call the youngest person ever to do something would be said to "not that big of an accomplishment". How would you change that headline?
To really put it in perspective right now is the hardest and most competitive chess era in history thanks to computer-aided practice and international popularity.
It’s not the most competitive world championship though, since Magnus opted out of playing it. If previous champions had similarly opted out of defending their championship at the age of 30 then maybe the average age of champions would have trended downward and this wouldn’t have been the first 18 year old champion.