You make many good points. However, not all "big dominant" companies dislike change and are stagnet, indeed, many of them are the ones developing and pushing the changes.
The Bell System and IBM of the 1960s were behind many of the social changes in business communication. Reduced toll rates and more sophisticated technology allowed the telephone to be a commodity than high cost specialized appliance. Centrex and DDD allowed someone to call another instantly compared to operator arrangements people were used to. IBM's reports and punched cards dramatically raised the volume of information being passed around.
There was much social criticism of the new world of phones and computers. People pleaded for a place away from the incesant ring of the phone.
The Bell System was huge. Some parts were better than others, some quite responsive, others sluggish. From reading responses, I don't know if NYC ever got over the past service crises.
IBM went through a relatively brief period of stagnation. It did get too bloated by hiring too many people to fit the IBM "no layoff" model and ceased being lean.
But plenty of small companies are merely followers of the big guys with no contribution of their own. IBM was mad at small companies that cloned the fruits of IBM's research (as in tape and disk drives), sold them cheaper, then complained when IBM made upgrades that hurt their clones.
My argument against the first poster was that it seems to be more of a triade against the traditional phone companies and not one based on the facts.
I am greatly suspicious when someone holds up a new invention and is upset that it isn't in everyone's hand the next day. The world doesn't work that way.