There have been times where Windows has had a negative connotation. I think Microsoft has a chance to turn that around with Windows 10. As Xandros has said, Microsoft is banking on One Windows. I think they have a chance, there is plenty of positive feedback with Windows 10 Previews, and HoloLens is bringing a cool to the product that Microsoft has always lacked.
If there is a stigma about "Windows" from a younger, tech-savvy audience, they are smart enough to know that Windows is Microsoft. Dropping "Windows" won't solve the issue. Making Windows genuinely cool will.