A lot of people seem to get these two facts mixed up.
<< Huh? Courts said that MS is a monopoly and that they have abused that monopoly. >>
Being a monopoly is not illegal, abuse of monopoly power and position is. That is what the courts determined.
<< Only thing they said in favour of MS was that break-up is too severe! DOJ very-much has a case against MS! >>
The DOJ has a case against the practices that MS made in abuse of their monopoly position, but any punishment
or remedy they come up with can only go so far as to address those practices and correct the companies behavior
in those areas that were restrictive of competition from other companies, or restrictive of consumers better interests.
The problem with the breakup idea was that some parts of the company do not have a direct link to the practices
that the court ruled against, and as such those parts would be unduly punished by such a remedy. While some
people might not care (or might prefer) an excessive punishment laid against Microsoft, that would also put the
company in a prime position to get such punishment reversed on appeal if they could show that the decision was
overreaching the actual remedy needed. Even the DOJ has to act in a fair and impartial manner in this regard.