indeed... it all gets back to having a plan. If you agree that you don't want to kill animals... do want to have a magnificent tank that looks better and better in time... then we must have a long term plan.
Most people will not keep a greyhound or a bull Mastiff in an efficiency apartment... and just because those that do still keep their dogs alive doesnt make it right or the dogs examples of optimal health and wellness.
Many aquarists admire the magnificent mature German, Japanese, etc aquariums...
These are aquarists that have room for say 5 mature corals and so they start with not more than say 8. They whittle out the few that dont fare as well or fall out of favor, then in 2, 3.. 5 years - they have a truly magnificent tank (50-100 gall in this example) with mature corals that look much more like they do on the reef... are more disease resistent... demonstarte behaviors usually not seen (types of polyp extension, polyp formation, planulation, etc)
By not stocking a tank too fast or too heavily, the animals do not waste precious energy on defense or recovery, but rather channel it into glorious health
Biotope displays also save you time and stress (less disease - Xeno or otherwise natural but stress induced from the unnatural crowding)
Put another way... if you say that you are that uncommon aquarist that does not empathize with these organisms as living creatures, has the money to treat the tank like a piece of furniture... and is willing to accept any extra work or mortalities to have a garden tank the way you want it - then that I can understand. I can even accept it. Its an honest answer even if I do not agree with the intentions.
But most aquarists are not that way. They just need a little reminder of how good things can be... and that we have an obligation on many levels here with the living resources that we admire enough to throw thousands of dollars of our money at