I would argue that almost every industry has been increasingly monopolized. Look at the historic number of players in every major industry - it's indisputable that the trend has been towards consolidation, not increased competition.
What's more - the companies that dominate various industries are majorituly owned by the same financial entities, which in turn own each other.
Think of the biggest players in each industry, and search to determine who owns the most stock in those companies. You will find the same organizations over and over again - Blackrock, Citadel, States Street, etc.
Capitalism is the reason for declining quality. The incentive isn't to make quality products and services - the incentive is to monopolize an industry, and then squeeze every last cent from the captured consumers. Line must go up!
Think of the biggest players in each industry, and search to determine who owns the most stock in those companies. You will find the same organizations over and over again - Blackrock, Citadel, States Street, etc.