Thanks for enlightening my sleepy mind BFEL, now I see some adequate points.
I agree with what Virtz said about not having them look like humans. IIRC the Brotherhood only express hatred towards Synths that look like humans - they call them weapons of war and mass destruction - but I guess they see usual Synths like normal robots. That would conflict with what Flying Dice said about their freedom to choose their appearence..but, well, remember Geths from Mass Effect?
From what I can recall, from their inception, to their sentience development, to the war against their makers, they never wanted or mentioned wanting to look like their makers. And I think the case for Geths was way more acceptable since they weren't designed as replacements for the makers. The constructor race, however, lost their shit on the first signs of sentience and tried to shut them down. Now that's racism and intolerance right there - Sentient Geths would get destroyed and won't even react because they didn't know what was happening (in the beginning - they later rised to defend their owners which would be murdered if they didn't surrender their Geths, which ensued a war later on).
In the case of Synths, Institute built them aiming at sentience and self-awareness, aiming at using it to hurt humans. So it is understandable that a lot of people will see and treat them like weapons.
What I mean with this is that I believe that the context of AI inception will dictate the public opinion more than the actual debate of wether 'synthetic lives matter'.
Of course, as Flying Dice said, this is all fiction. Another example is the movie Ex Machina, which it's all well and dandy when the girl looks like a machine. But when she dresses and looks like a human you can't help but think "Wait..is this right?". At least that's the reaction from everyone I know who watched it.
Now, if we were to transfer this to real life, I don't know yet where I would stand. I'd be way more acceptive of things if the rule was "You're not human, so you shouldn't look like one".
However, I'm not sure if we ourselves have laws to prevents us from doing surgeries to look like an animal, or something. Since I sexually identify myself as an attack helicopter, I guess I should try it out.
