I feel uniquely qualified to expand on what @Troy’s saying here, since my “main” arm position and picking motion is almost identical to the first video. Depending on how much “wrist extension” you apply at the bottom of downstrokes, and how much supination your arm position has, this technique can result in pickstrokes that are “curved” in the crosspicking sense, but where the curve still “terminates” below the adjacent string. The more your arm position is pronated and the more “wrist extension-y” the movement is, the more effective it is for fast crosspicking (but the wrist movement is still subtle, I’m contrasting with a DWPS forearm-rotation technique where the wrist flexion/extension component would be even more subtle). The more your arm position is supinated and the more subtle the wrist extension component is, the faster you can crank the speed, at the cost of requiring a jerkier supplemental wrist extension movement to try to do a “crosspicking” string cross. A key to me in how this feels, and perhaps you can relate, @kcyrowolf, is that I’m usually not even really thinking about the wrist extension component, it feels like an almost involuntary consequence of the “camming” motion of the tip of my radius bone against the base of my wrist near the thumb each time the forearm makes its subtle rotation in the pronation direction.
One experiment you might find interesting is to try that picking motion with a slightly more “flexed” wrist in the gypsy style to see how much you can crank the speed. Then, after you have a feel for higher speed in that position, try to recreate the speed in your “original” position, or even in a slightly more pronated position.
In short, this position and motion is interesting because it sort of straddles a conceptual line where it is very conducive to crosspicking when it looks like your video, or even tilts a little in the “pronation” direction; but it’s also conducive to blazing fast DWPS when it tilts more in the “supination” direction (and maybe adds a little flex to the default wrist position). And there’s a third cool thing: when the essence of this motion/position gets tilted in the “pronation” direction past crosspicking, to a point where the default wrist position is more extended, and the curved pickstroke “escapes” on downstrokes but remains trapped on upstrokes, it provides more margin for error for “fast” UWPS. I’m at a point now where I’m trying to develop fast fulltime crosspicking in the “middle” of these positions, and the drawback is that the margin for error to cross the strings in either direction is kind of small, which means things I’m accustomed to do for dynamics with a one-way pickslant have a greater chance of throwing off my accuracy, but I think it’s still do-able. My tendency as I try to reach my limits with this is to “default” to the fulltime crosspicking motion (with the “midpoint” of the curved pickstroke pretty much directly under the target string), and for extreme speed stuff, leaning back into the “UWPS” mode of this technique (with the “midpoint” of the curved pickstroke crossed after the downstroke has picked the target string and is on its way out to the “escape zone”), and at the highest UWPS speeds, the elbow motion might click in slightly, creating a more “classic” straight line UWPS motion.
Mind you, when I’m not actively working on that stuff and my “lizard brain” takes over, I revert to a fast DWPS motion that is basically the motion from your first video, but with a slightly more flexed default wrist position and a curved stroke that stays buried at the bottom of downstrokes. (Edit: I guess when I say “default” I mean “at the top of upstrokes”, and the total amount of wrist flexion/extension movement in all cases for me is pretty small, though it’s slightly larger when I try clear the strings on downstrokes from a setup that’s more “DWPS” oriented)
TL;DR: The essence of the motion in your first video has tons of upside for crosspicking, UWPS, and DWPS, and can be “tweaked” for any of them as described above.
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