While this is a sad ending to a circus with a long history the picture is not so grim in its entirety. Many of these talented actors will most likely find their places in other circuses across the world. Some might even become part of Cirque du Soleil.
Political correctness caught up with tradition, it happens often nowadays. The optics on keeping animals for entertainment have grown dim in recent years, thanks to the corporate treatment of animals-as-attractions. Instead of treating the animals with respect, they kept the animals in squalid conditions and treated them poorly (think SeaWorld). Profit chasing turned into public outrage, then regulation. The industry brought this upon itself, but this was inevitable. People did pay to watch gladiator events in the past, and parents would bring kids to beheadings and lychings, they would even pack a lunch

Tastes change over time; this was a victim of that.
Sucks for the trainers and performers though. These are unique skills, dying arts, so to speak.
They should have adapted. Lost the animals and focused on human acts like the Vegas circuit.