Here's my experience with exactly the two kind of binoculars you suggest: 8x32 alpha vs 8x42 "excellent-but-not-alpha".
My first "good" binocular was a Zeiss Conquest HD 8x42 (I guess it fits perfectly in your definition of "excellent 8x42"). Really very nice, but after a while I realised that it was a big mistake, because it was so heavy that I simply couldn't be bothered to carry it and started leaving it at home until one day I realised that it was pointless to have a great performer that it was too heavy for my use (I use it mainly while trekking or lots of walking involved), so I sold it.
Now my main binocular is a 8x32, sometimes I carry an "alpha" (Swaro ELSV), sometimes I carry an excellent one (EII or Traveller ED). Never a single second of regret for missing the view through the Conquest HD 8x42. Not a single second.
I don't know if this answers your question of whether or not a non-alpha 8x42 can provide an equal or better view than an alpha 8x32. I simply couldn't care less about what it provides, what matters for me is what I need most of the time, and this is an 8x32. I'm sure the Nikon WX 10x50 is an impressive device, its FOV at 9º is wider than most 8x42, even 7x42 out there. But even if I had the money I would not want one as a birding binocular, I'd still rather take a 8x32, even if it is a more mundane device like the Opticron Traveler 8x32 (of course I'd love it for astro, but this is BF, not CN
).
This is actually the reason I'm 100 % sure I'd love the 8x42 SLC, but I don't think I want one, because is as heavy as the Conquest. So, even if I know it's an amazing device, I won't use it most of the days, and I simply can't justify spending +1000 € on something I won't be using (I don't mind having an ELSV or an ATS65HD, because I use them every day).
Like someone pointed out earlier. I'd rather have an 8x32 for everyday (at around 500 g) and then a dedicated but heavier low light (7x42, 8x56, even 10x50) than carrying 800 g every single day of my life, for the few times I need the extra punch in low light situations.