Well as your parent post indicates MS did a lot of bad shit. "oh I screwed you mommy over again and again, no worries, no foul, now we are chums, lets be all buddy buddy and sing Kumbaya in a circle" doesnt work all that well in practice and neither should it. That is what learning from past experiences is about.
When a behavior gets institutionalized, it is likely to repeat more often than not. It requires exceptional evidence and time before for trust to be regained.
A person rises up in a typical institution by following and embracing its institutional patterns. When they have their back to the wall how unlikely are they to fall back on their old patterns, heck they neednt even have their back on the wall.
Now if someone gets get screwed over by them, no ones more to blame than themselves. As they say, "fool me once ..."
It is entirely possible that someone else does similar damage to your business in an unethical way, but if one goes to a repeat offender and gets treated that way, the shame is on him / her.