Sure, that is the role of the courts. However, in this case, that distinction rested on the definition of what constituted a certain peice of technology and the ability to predict how that technology was going to evolve. The courts had no way of knowing the answer to this question. To their credit, I honestly doubt the companies themselves even knew the answer at that time.
This situation was very different than when an oil company uses their monopolistic position in refineries to choke competing exploration and retail companies. Or when a manufacturer of telephone equipment uses the profits from its monopoly in that business to drive out competitors in its telephone service business. Clearly, in these scenarios, it was clear (and remains clear) that the monopolists were using resources from one business where they were clearly dominant to out-compete other companies in separate (even if adjacent) businesses.
Technology is a very tricky area for the law largely because it is fast changing. Situations are cropping up far faster than the laws can be modified to address them and so the courts are pretty much forced to sand-off the edges of existing statutes that were designed for other situations and hope for the best.
You seem to be saying that the evolution of technology over the next 20 years had something to say about whether Microsoft was abusing a monopoly situation at the time of the trial. I don't think that's a valid way of applying the law.
Furthermore, a big part of Microsoft's motivation for making the browser "part of the OS" was exactly to try to blur that line for the court. I am therefore highly skeptical of using "it's now part of the OS" as a reason that the court got it wrong.
This situation was very different than when an oil company uses their monopolistic position in refineries to choke competing exploration and retail companies. Or when a manufacturer of telephone equipment uses the profits from its monopoly in that business to drive out competitors in its telephone service business. Clearly, in these scenarios, it was clear (and remains clear) that the monopolists were using resources from one business where they were clearly dominant to out-compete other companies in separate (even if adjacent) businesses.
Technology is a very tricky area for the law largely because it is fast changing. Situations are cropping up far faster than the laws can be modified to address them and so the courts are pretty much forced to sand-off the edges of existing statutes that were designed for other situations and hope for the best.