For more information on why I think democracy makes things more ethical, see the other reply I left in this thread.

But to address your counterexamples:

1. None of your examples are countered by private organizations, they can and do make decisions motivated by ideology all the time. In fact, whenever you see real news of companies doing or supporting insane things, you can almost certainly be sure these companies are privately owned and that the insanity is passed down from the top.

2. For the rest of companies that really don't care about ideology and only care about making money, there's the argument that making money isn't a neutral standpoint, but one of chaos that just supports whatever is profitable. If putting people into concentration camps based on their race became culturally accepted, you know that discount stores will start selling clothing with hateful graphics, news sites would put up real-time counters and tech companies would develop exterior cameras with racial scanning and automatic reporting to cater to consumer demands.

3. Most crucially, democracies usually have a moderating effect on people's viewpoints. It's trivial to find companies ruled by crazy people with many normal subordinates going along because they need to make a living. It's a lot more difficult to find one that's stacked with insane people that produce insane decisions on average. Democracy lends itself to compromise, authoritarian rule lends itself to sycophancy that reinforces whatever comes from up top, no matter if it's sane or sensible.