That's certainly exciting news if it turns out to be correct, but there are reasons not to get your hopes up just yet. The forum reports that the truck is in the early stages of development, and it's still being decided whether there's enough of a market for it.
From our perspective, such a model is neither a dead end nor a shoo-in. Certainly there are people willing to buy fast off-roaders, as the aforementioned Raptor and ZR2 have shown. Also, Jeep has proven that people are willing to spend a lot on Wranglers, both from the factory and on aftermarket parts, so an even more expensive model wouldn't necessarily put people off. So those are two important points in favor of a fast Gladiator.
Points against a fast Gladiator start with the existing Gladiator Rubicon. While it isn't necessarily designed for bashing dunes, it does come with a huge amount of trail-ready equipment already. It has differential locks and anti-roll bar disconnects, big tires and burly shocks. On slower trails, it may already be as capable as the Colorado ZR2, which would be the closest competitor to the hypothetical high-po Gladiator. And since the Gladiator Rubicon will be available with comparable engines to the ZR2, would something more potent be necessary? It would seem that to further differentiate, the Gladiator might need more power. That's certainly possible by way of a V8 transplant, but that would mean a lot of money spent on getting the engine to fit, making it reliable, getting it emissions compliant, and ensuring the drivetrain is strong enough. All those costs would make it harder to get approved.
We may sound a bit pessimistic, but don't get us wrong, we would be excited to see a high-speed Gladiator, or any other Jeep for that matter. But we also want to be realistic, and there are certainly some significant hurdles to bringing such a truck to market.