Rims are made of softer/weaker materials than spokes. A smaller hole is not a benefit, its a disadvantage. Eyeletted rims are already known to offer durability benefits over rims where the nipple goes straight into the rim. And the eyelet helps spread the load over a greater area. Something like a traditional straight-pull spoke poked straight through a rim would cause a considerable greater load concentration than even a regular nippled build. Unless the rim is reinforced at the spoke seat, I foresee regular pull-throughs.
I was actually thinking the same thing. But it seems that rather than making it two different pieces, as in a nipple that seats into the rim, it could be designed with a gradual transition of rim material at the right heat treatment, or some localized material blend (don't ask how, I have no idea). I actually don't know how the models I've mentioned are built on the inside of the rim.
If the DS spokes get thicker where they attach to the hub, the center line of the spokes has to be moved further away from the cassette. Even more so in a crossed pattern.
Ok, so maybe that's why on the 7801, the rim was asymmetrical, where the spokes entered to the non-DS of the rim. On the hub, they may have had to be 1.5mm further away than a spoke without a nipple.
Maybe I'm just a fan of how it looks LOL