Because it is a world without magic and to add another piece of evidence..it's a separate ip, this would be like having Ewoks make a cameo in Back to the Future. She described a stereotypical "science world".
I couln't disagree more with your point of view, or your arguments (with respect). There have been easter eggs in Dragon Age Inquisition from Mass Effect (the krogan trophy head), they don't have a shit in common but owned by the same devs and it's a FUN idea. So, doable. Cyberpunk was long way into production since 2012, so why devs wouldn't put this easter egg in TW3 in 2015? Breadcrumbs & sinergy in action.
Then there is the matter of magic. There's no point in the destiny's location being magical or not, but from departure place. Ciri can appear in any dimension through a portal, since the non-magical scifi world she describes in TW3 (99% Night city), to our very same realm, the Earth. Like when Geralt breaks the 4th wall at the end, or in the anniversary video, and talks and looks to us. If he can be conscious of our realm, Ciri definitively could travel here, or, more probably, to NIGHT CITY.
You mention Mike Pondsmith being against this. Just like Andrej Sapkowski could be with many pop references or licenses devs took that weren't on the books... CD Projekt will respect the soul of this, but making its own. Pondmith is dreaming awake with this shit happenning.
Why do you have to cut off people ilusions? You speak as your word were the truth. Let us dream.
CIRI IS IN