Microsoft did not make its mark as a builder of great things, but as a very successful bundler of good-enough things.
Eventually by the mid-90s an argument could be made that Microsoft was making the best PC software in its class. Not because it had suddenly found the ability to develop cool, innovative products, but because everyone else was dead.
Still, outside that monopoly, there is a clear distinction between Microsoft products that can trace their market dominance back to DOS, and those that can't. The former make money, the latter lose it.