There will eventually probably come along a better fighter than Jones. Khabib was undefeated as well, never got hurt, and only lost one round his whole career. So there will be more dominant fighters than Jon.
But no one in modern MMA can ever beat his two record:
1.) Youngest champ.
2.) 15 title fight wins.
Jon came at the perfect time. The UFC was relatively young, divisions were thing and the roster was about 1/4 it’s current size. The days where you get a title shot in your 3rd fight (unless you’re a champ from another big promotion) are gone.
Even undefeated fighters usually need to be 7-0 in the UFC to get a title fight. That 7 wins might take 5 years because if they are great, they deal with horrific ducking (see Umar currently begging for a fight from any BW on the roster and getting nothing lol) and just deal with the regular inactivity that has become normal.
So even if a greater fighter than Jones comes along, there just isn’t the chance to win 15 title fights anymore. There’s not enough time. Most deep divisions can’t even get champs under age 30 now, much less a 23 year old.
TLDR: Jones will always have the GOAT statistics, similarly to old school baseball pitchers with like 500 career wins, because he came along at the perfect time in the sport.