I personally would not emulate a game that Nintendo is currently selling in a readily-playable form (unless I owned it already). Used games don't count, because those a) don't send any money to the original devs and b) become increasingly scarce over time.

The problem is that in practice Nintendo only makes a very small portion of their back catalog available for purchase at any given time. The only Zelda games from previous generations that I can play on my Switch are Zelda 1, and (soon) Skyward Sword. No others are available.

If Nintendo made their whole catalog available for digital purchase (or even better, as part of a subscription) then I wouldn't emulate any of it.