It's not really an outlier, there are plenty of sports where there are long standing world records, some of them have been broken recently but stood for a long

It's not really an outlier, there are plenty of sports where there are long standing world records, some of them have been broken recently but stood for a long time. It's just the nature of having so many sports, not every sport will attract as much talent resulting in having a much bigger impact when that world class talent appears (Zelezny). Usually these sports are technical in nature and thus harder to dominate through sheer improvement in nutrition and muscle power. Take for example Usain Bolt, he competed in the sprint but if he focused his career on some other less popular athletic sport he probably could have been WR holder there as well. If you combine this with the fact that it's possible there was more doping in the past (especially 80s), you can get these incredible world records that stand for decades.