In this video essay, Rossatron explains the rise of shaky cam and why it's so prevalent in modern action movies. He doesn't defend its artistic merit (because that would be impossible), but he explains why the changing industry and the actual economics of film-making have made it so popular now. Long story short: doing a proper action sequence is difficult and expensive and shaky cam makes it easier and cheaper.
Apparently the final six-minute action sequence in The Raid took 8 days to shoot, and the video claims they sometimes shot between 17-26 hours per day. I don't even know how you shoot 26 hours in a day, but I guess I'd use shaky cam too if it meant I could avoid having to bend the laws of spacetime.