Debatable and in many cases (N64, Saturn), it is not. In my experience, even if an emulator runs well, it's still a worse experience than original hardware because it introduced unavoidable input lag (in conjunction with display input lag) that can make certain games very difficult to play. This mostly applies to retro games from 32-bit era or earlier which were made to play on CRTs with 0ms response time.
Money in all likelihood. I'm not condemning the emu devs for that, but let's be real.
The one on the right of course (if it was a choice between Wii U and PC, Switch portability convenience trumps them all)...but the entire JPG is low quality and making the one on left look worse and blurrier for no reason. A direct capture of Wii U, although low res, should look crisp regardless. But I suspect people will keep pulling out that degraded image in these arguments over and over.
This is neither here nor there, but I don't believe this for a second. I think there are far more lurkers on this board who know they can't openly boast about piracy and who fully intend to pirate games on CEMU than there are people interested in CEMU from a project standpoint who will then emulate the games in a legal, proper way. To each their own, it's none of my business, but I don't think we should lie about how the forum is full of morally upright saints.