I never said it wasn't tierable, I said nothing suggests it scales to their physicals, or that the Titan even possesses said reality warping.
The Titan doesn't sustain anything. The Fountain does, and the Titan lacks many attributes that the Fountain has, such as range and reality warping. If it lacks these basic qualities, why should we assume it has AP comparable to the fountain's ability to sustain and create Dark Worlds?
It matters because it demonstrates that the Titans lack many attributes that Fountains have, so you can't just say the Titan scales to the fountain's creation and sustaining abilities.
They're similar in some ways, but they obviously are not fountains, and they lack many attributes of the fountains, as I just went over. It's actually pretty much the exact same thing with NEO. There's a lack of evidence to scale the reality warping to physical strength in both cases, except in this case the Titan isn't even the one performing the feat. We don't have any evidence to say that the fountain's creation hax = Titan AP.