Sharing isn’t the issue. The emulator was profiting from it.

I wrote about sharing but even profiting from it should be legally permissible.

If I copied your house key and sold it, would that be alright?

Of course not. There are laws against that. Laws that are not copyright laws.

but I don’t lie to myself that it’s morally defensible.

Oh, sorry, I thought this was about legality. If we want to talk about the morality of evading copyright we should also about the morality of copyright itself, how it historically came to be and whose interests it was supposed to serve (it wasn't made to support creatives). Actually there is surprisingly little evidence that the introduction of copyright increased the incentives for creatives to publish or made them wealthier (except a select few). I think there is a better case to be made for the morality of sharing creative works unlawfully than for limiting the sharing of those works for a century after their creation.