In all these cases, the largest companies became the most unprofitable. Most striking is the turnaround in telecommunications. But the financial markets favor such upstarts. Scale no longer provides the same benefits, even in telecom. There's room at the top.
Most economies of scale have limits.
Scale is still important. But the large number of telecom providers competing for business globally and locally shows that many firms have sufficient scale, and that the key to success lies elsewhere. The same is true of airlines, autos, steel and most other industries. You don't have to be big if you have big connections. Telecom systems, and many other production systems, are now open and interlinked.