What are your views on emulation?
Without emulation then thousands of games would have been lost to time, especially PC games from the 1980s and 1990s. Companies are increasingly using emulators (360 BC, Virtual Console, PS Classics, NES Mini, etc.) to bring old games to newer audiences. It's also necessary for preservation, hardware and physical media requires a lot of maintenance in order to keep them working: batteries need to be changed, cart/disc reader may need to be replaced, PSU may need to be replaced. It's a lot of work and it's not practical way for average games to enjoy old games.
What benefits does emulation provide?
Preservation and accessibility.
Does it impact game sales?
I can't tell you how much piracy affects legal distribution methods for old games. For new games, simply illegaly downloading the game onto your console (piracy) is a much bigger issue than emulation and definitely more widespread. Emulation for new games is still a work in progress, games are more or less in working order and you need a pretty good machine to run the games too (nevermind the games being optimal). By the time the mainstream starts emulating games like BotW and Persona 5, those games will already be years old, whereas pirates are currently using modded systems to play those games at console level right now.
How do game creators feel about this?
Can't speak for them.
What are the legalities and ethics around emulation?
Emulators are legal in the United States due to legal precedents set when Sony sued two emulator developers. How you obtain the games is a different matter entirely and depends on the laws of the country you live in. In my opinion, if you already own the game in some form (official emulation, physical copy, digital, etc.) or the purpose is educational then I don't think that emulating is unethical.
What percentage of those that use emulators are engaged in privacy?
Probably most of them, however it worth noting that companies behind legal emulators are also engaged in piracy.
Are there sources of data to support this?
Sony Computer Entertainment America v. Bleem 214 F.3d 1022 (2000), Sony Computer Entertainment, Inc. v. Connectix Corporation 203 F.3d 596 (2000).
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