It’s always been popular among athletes and weight lifters but now nootropic influencers have gotten ahold of it. It’s one of the few supplements with robust scientific evidence of a strong effect but that’s in athletic performance not nootropics.
No, creatine has been studied for decades and it’s been part of fads before (I remember Mac making a joke about creatine shits in It’s Always Sunny in Philadelphia a decade ago).
It’s just resurfacing as a general health fad/marketing campaign.