I cant see how the hobby is, or ever was, or ever will be UNethical or cruel.
I think all fishkeepers whether experienced or newbies, have the moral intent to keep their fish healthy, whether the advice or knowledge they have is correct or not, and whether their fish last 1 day or 10 years, their ethical intent was to do the best they could for their fish.
Isnt that what ethics is ?, the intent to do the right thing?
Is tying a bulls balls in a knot to make it buck for sport ethical?
Is putting a saddle on a horse ethical?
Is docking a dogs tail or ears ethical?
Is keeping a bird in a cage ethical?
The list could go on and on