Terrible compared to what? Another decent $89 porro?
I don't find "flare" control to be terrible in either the 6x30 or 8x30 but the bin is vulnerable to veiling glare stray light especially when viewing above the horizontal.
I think this is because to upper prism can see the lower outside edge of the objectives so there is a stray light path. This shows up when it catches bright light (which most of the time it doesn't).
You can see this if you view the Yosemite from the objective end with the hinge downward outside (uniform bright light helps). You can look in through (from your point of view) the upper right and upper left of the objectives into the prism housing.
I think there was a trade off in prism size (bigger) and baffling that allows this to happen but for horizontal viewing that is looking at the ground you tend not to get much light in at that angle. If you look up at a significant angle (30 to 45 degrees) at a tree surrounded by sky you can see this effect. It's not a direct path to the eyepiece or the optical path but I suspect with some multiple scattering you get veiling glare: reducing the contrast across a portion of the field.
The effect is the same in both 6x30 and 8x30 as the optics are essentially the same: with the same size enclosure and worse eye relief I suspect only the eyepiece focal length (and associated aperture stop, perhaps) have changed. And that wouldn't affect this sort of stray light issue.
BTW, unlike some other comments about the 8x30 being ussuitable for use with eyeglasses. I find the 8x30 with its specified 14mm eye relief that sounds too low works fine for me (just see the full FOV) with my eyeglasses (which are quite close fitting).
Aside from that the 8x30 has a larger AFOV but a smaller FOV and the image is a little dimmer as might be expected. The larger image and the reduced brightness both make the 8x seem less sharp than the 6x. But it's still a decent performer.