The thing is that Steam doesn’t have a history of shutting down a significant fraction of games they have available by themselves. Hence people don’t criticize them.
Also you can (not saying that you should, I personally don’t trust Gabe) put some tust in a private owned company if you trust the owners.
In case of public companies they are forced by law and major shareholders into making shortsighted decisions and prioritizing profit only.
He doesn’t overact it. He’s genuinely and rightfully salty when it comes to companies and governments screwing us and him over.