As I see it things don’t exist on an exact scale where you can clearly separate one from the other.

But rather a continuous spectrum of existence where everything is connected as one thing but still has different aspects/ properties to it that contain enough information for us to differentiate.

A bit like a color spectrum where the color blue is not exactly defined and might be more of a dark purple to one person but most would still agree it’s a completely different color from yellow for example.

All this to say that in my personal opinion the mind upload would definitely be something different but you could say the same every moment when your mind or the particles that make up your body make even the slightest change. (Like a minimal change in hue could be classified as a different color)

The question is how much different it would be? I think it would be quite a difference since so much of what makes us human is anchored in our biological anatomy. Our imperfections and desires, social, biological or sexual they are very much a product of our physical bodies.

Would we try to keep them somehow or would the mind upload be like a perfect mind free of impulses and vices?

I agree that ethics is a very puzzling field. I have my own theory that might be a bit to long to elaborate here. But I must say that over all the judicial system is doing a surprisingly good job in having a nuanced and differentiated view on ethics, at least in theory. How we differentiate murder from manslaughter for example is quite an advanced level of logic, that I sometimes miss in other branches of Society.