The topic of the thread was _Microsoft_ doing sleazy things, specifically displaying fake error messages when it sensed a competitor's product being used (using obfuscated xor encrypted self-modifying code to hide their activities). Microsoft and their execs, as illustrated by this and the countless other examples _are_ sleazy, ruthless, cheats, who did/do not believe they had/have a superior product that could/can win on its own, so had/have to resort to sleaze like this, and other sleaze like forbidding vendors from selling any other OS, or the vendor would have to pay much more to MS. Some of their actions were illegal, but escaped consequences (in the US) due to stepping their use of campaign contributions (legalized bribery) and lobbying after the anti-trust case was brought against them.
But, even factoring horrible companies/executives like those in the tobacco and petroleum industry, Microsoft is still pretty high up in the list. E.g., without a logarithmic scale, you wouldn't be able to even see the data points for most grocery store companies when plotted on the same sleaziness graph as Microsoft while Microsoft/their execs would probably still show up on a graph that included fossil fuel and tobacco companies/execs.
As for, "feature not a bug", the ongoing human caused collapse of every ecosystem on the planet and the resulting mass extinction shows that maximizing profits at all costs is a bug. The existence of favelas walking distance to private estates show that the way this system concentrates wealth is a bug. Even on the level of Microsoft stealing from and killing off competitors, we lose. Many Microsoft competitors had better products and were far more innovative (hence Microsoft needing to steal from them / eliminate them)-- only Microsoft gained by their demise.