What are your views on emulation?
Emulation exists both as something I used, and may use the future, it exists to service a need to do things quickly when needed in my eyes.
What benefits does emulation provide?
Honestly Piracy, people can act like playing games more detailed, but piracy is the key benefit.
Does it impact game sales?
Yes, I honestly believe so, since I am myself literally skipped GBA (Otherwise I would have bought it), because of emulation. Just like many people who are waiting and paying for CEMU development are not going to buy Wii U or Zelda.
How do game creators feel about this?
They hate it, evidence has shown that many large companies hate modding a console and emulation, some indies are bit nicer about it, but why would someone want their work treated for free.
What are the legalities and ethics around emulation?
If it is without the ownership of the software it is illegal, I do know backup something is considered legal. However the sharing of said backup is illegal (see court trails). Morally it gets a bit grey, because some games are harder to find, and etc, however large percentage I imagine are using it illegally. (However like jay-walking, if it isn't actively targeted people will not treat it like a crime.)
What percentage of those that use emulators are engaged in privacy?
I imagine the percentage of people who have used emulation 100% morally correct is somewhere between 1-5% of people using emulators. That means they have never pirated single game they didn't own.
Are there sources of data to support this?
Sadly don't think any study has been done on number of legal piracy.