We as a species built our civilizations on an economy of suffering. Trading work product is just an exchange of suffering, and those who can best exploit the suffering of others build the most power and influence. We can extract a lot of value from the suffering of animals. It might be pain and death for food and clothing, forced labor to save our own backs and legs, scientific discovery through experimental suffering, or just the confinement of something pretty for a bit of amusement and companionship.
Empathy is the skill that allows us to develop morality, but compartmentalization is the skill that allows us to ignore empathy and commit violent acts of selfishness. Whether it's caged wild animals, factory farming, fast fashion slave labor, homeless children mining lithium and cobalt to make batteries for our devices, it's all a form of violence that we condone and support.
I don't know that I would call a caged pet bird violence, but I certainly think it's cruelty. Especially when they clip the wings.
Once went into a local pet store to get some dog treats. They had a bunch of birds that must have had their wings clipped, because they were all crowded into little open top acrylic boxes. It was just awful. If I thought contacting the local humane society would do anything, I would, but I've dealt with them before and I know they wouldn't do shit. And it's an established store that's been there for decades, so I'm guessing anyone in authority who might know about it does.
Anyway, I never went in there again and I badmouth it every chance I get.