I agree we could make an empirical study that would shed light on the issue if we took a consequentialist approach. That would be interesting.

Regarding the machine, precisely as you've set it up, no, I don't think it's immoral. Part of this is because humans, as social creatures, really need someone to know and care about them especially during development. But, anyway, if we don't think about that, no, if you turn the machine off, or don't switch it on, or a woman takes RU-486 to avoid implantation of a fertilized zygote, or doesn't get pregnant every menstrual cycle, or a fertility clinic discards dozens of fertilized eggs, etc etc etc, the developing zygote is not a person. Unless we need it, terminating it or not having it in the first place is morally neutral.

The only argument I see for it being a moral issue is if humans are the kinds of creatures that cannot apply moral worth to babies unless they also apply moral worth to fertilized eggs (or some other pre-personhood developmental stage). If that were true even though it the decision might not be intrinsically a moral issue, the stance taken might be inextricable from moral virtue and thus, given that moral virtue is good, it would be immoral to muck with it.

But given that we can switch on and off ascribing moral value to people even with other living adult people (most notably in cases of genocide) I very much doubt this could be the case.