"Competition is the essence of capitalism, yet it is dying."

Sorry to have to point out something that should be blatantly obvious, but no. The essence of capitalism is capital, the accumulation of wealth in private hands that own the means of production. And capitalism has a nasty tendency toward fewer, more powerful players as they gobble up market share, muscle out competitors, erect legislative and logistical barriers. This is what capital does. It buys the power to continue itself. What you are seeing is absolutely capitalism running its normal course.