Breaking up Microsoft would yield a slew of benefits. Smaller companies could focus ruthlessly on a single line of business. Netscape has successfully spun out several business units and joint ventures. More and more, Microsoft is holding back important improvements for fear of cannibalizing other products. Bureaucracy has begun to gum up the Microsoft machine.
Smaller companies are more nimble.
Improved returns for shareholders. Such as lower long-distance rates and helpful new services. A Microsoft breakup would do the same for personal computing. Because then certain business segments would be forced to survive on their own merit. Certain unprofitable segments.