I live in the Netherlands, so it's probably a lot different than in the US. Last week the government agreed on a new animal keeping law. As of 2023 it's illegal to keep animals in cages. More in detail it says that animals can't have pain or discomfort from being locked up. The law is made for livestock farming, but will also effect the pet industry. The main point is that animals can show their natural behavior as much as possible. The government is still working on how it will work exactly and what all the requirement will be. But it will influence the saltwater tank hobby for sure. I don't know how fast the US will pick up on this, but it's likely that they will eventually.
As for my personal opinion on cruelty in our reef tanks, I think it's a very difficult matter. I did buy a reef tank because I like to recreate a natural environment to keep animals in. I think it's a lot less cruel than keeping a rabbit in a cage. But I'm not a saint, and I'm guilty of keeping a (small) tang in a tank that most people consider too small. I observe my tank daily and my fish show normal/natural behavior. My livestock is based on balance in my tank, so every fish can live peaceful and show their natural behavior.
As for my personal opinion on cruelty in our reef tanks, I think it's a very difficult matter. I did buy a reef tank because I like to recreate a natural environment to keep animals in. I think it's a lot less cruel than keeping a rabbit in a cage. But I'm not a saint, and I'm guilty of keeping a (small) tang in a tank that most people consider too small. I observe my tank daily and my fish show normal/natural behavior. My livestock is based on balance in my tank, so every fish can live peaceful and show their natural behavior.