Before anything, here's the obligatory "Anti-cheat software is a huge security risk and violates privacy rights and therefore has no business in any game, no matter how bad the cheating ever gets" disclaimer. I am glad XIV is one of the (sadly fewer and fewer) big online games that actually is considerate of this, and it should stay that way.
Onwards to the topic of Ultimate cheating specifically:
Since Square does not sanction or endorse the World First race anyway, and it is a community-driven thing, the biggest reaction is likely going to be complete radio silence on those races from SE. The community will bickerabout it all and that's it, rinse and repeat at the next Ultimate. But as there is no way to be 100% certain if someone's cheating or not, and never will be, we are just stuck with this situation and better get used to it. I personally can't even muster much rage anymore about it. So yeah, someone cheated at the world first race. Just like last time. Does it impact me playing the game? No? Alright, moving on...
What I think is interesting is how some are trying to be very reductive about Ultimates always in light of these cheating incidents. It is content to be tackled by anyone that wishes to, at their own pace, and on their own terms.
And so, no, people using cheats in the world first race is no reason to cut back on Ultimate content. I know Yoshi-P threatened to do so, but that is misguided and if I am honest sounded more like a gut reaction of someone who was - understandably so - emotionally upset at the situation back then.
But some bad actors with no interest in Ultimates to begin with like to claim otherwise, out of an unfounded hope that cutting Ultimates would get them more of whatever content they like the most.
But an Ultimate is way more than just the World First race. I do not care if someone cheated at the game for them to be the first to clear it, I care for eventually getting around to clearing those fights myself.
Even the prevalence of certain cheat tools in PF would be no good reason to cut content they apply to, cause there might still be an untold number of 8/8 statics that never show up in PF that do the fight without those tools. Collective punishment is not the right call, ever.