I just figure that the simplest explanation (Occam's Razor?) is that the Syreen have special perks that Earthlings don't. Psychic abilities, and other unknowns.
That makes them less pure. Less crude. More complicated. The Arilou would like to dissect a computer without any add-ons attached. No sound card, no DVD-drive, no network card, no zip disk drive, nothing. Just the happy old motherboard and processor, snip snip, doodly doo.
The Arilou, after all, do say that they admire how pure Earthlings are, how unspoiled.
It's easier to take apart and tinker with something that doesn't have these unnecessary extra components hard-wired into it. Sure, these extra components might be handy someday. But what about right now, when you're trying to tinker with the motherboard itself and find a way to make it impervious to unfriendly moisture/Orz. Better not to bother with having to unweld all them pesky add-ons.
Logged
We are the Ur-Quan Kohr-Ah. Our nature, the fulfillment of our fate requires your destruction. You are filth. It is now your time to be cleansed.
hmm... maybe the idea was that the syreen were too great a risk because if only one of them found out, then the others would begin to smell too, because of the telepathy? So it would require far more vigilance... As it stood, the arilou didn't need to worry too much about humans as a whole when that lieutenant locked himself up in the room with the androsynth computer.