[MEDIA=twitter]641991169312989184[/MEDIA]
https://archive.is/zokZI
Okay, this one requires a bit of tech sperging, so bear with me:
Wu is technically correct on this one, as meshes generally aren't half as huge as textures most of the time, given most of the time they are geometric shapes that any mesh worker worth their salt will use as few polygons as possible to form (unless quality is absolutely required for finer detail), but usually, this is correct, as meshes are generally rendered using the CPU, and the video card/graphics chip handles the texture work.
The caveat is that on portable systems, the CPU/GPU tend be one and the same unit, much like a low end gaming PC, and thus even a moderately mesh filled game will tax the computer because it drags down the processing cycles needs to keep the OS running as well, which leaves the textures forced to use the system RAM (which is SLOW) as a fallback, meaning even something really simple like Minecraft can render like ass.
An even better example to use would be Morrowind, a game that can bring even modern systems to their knees depending on the amount of meshes due to the poor optimizations to the NetImmerse engine, which dumps all the work on a single CPU core only, so even a modern PC could be brought to it's knees by a high quality mesh laden mod, even if the graphics card is amazing.
As applied to Wu's own game, assuming Wu's earlier comments about having to use a really inflexible skeletal framework for the characters still hold true, Wu probably bolted a TON of meshes to the frames of the characters, especially if he wanted them to resemble his preferred art style exactly (likely, as the characters like Holiday are miles above everything else in the game in terms of apparent mesh quality), so the tl;dr is that on a system of limited power, the mesh work is optimized very piss poorly and even if Wu managed to port R60 to Apple TV (when it already had framerate drops on iOS), that means the problem would be even worse on an even more limited platform in terms of mesh rendering power.
Note: Wu showed us the mesh framework overlays for the new armor on the character models awhile back in a tweet photo, which only add more mesh details to the characters, which will likely make this problem worse.