Well, part of the blame for this has to be laid on the people who gather caviar. I watched a show about this recently, and they actually kill the mother fish to gather the eggs (caviar)!
It’s been quite a few years since I grew up on a farm, but I clearly remember that killing the mother was not an optimal way to raise more babies! Chicken eggs would be awfully expensive too, if we killed a hen to get each egg!
I don’t understand why someone can’t invent a caviar-gathering tool that you stick up into the female fish, suck out 90% of the eggs (leaving about 10% so we have new baby sturgeons next season), and then turn the female fish loose back in the lake. Then you’d have a renewable source of caviar for future years. Is there some reason this wouldn’t work?