Even in the U.S. case their intervention in the Balkans met its intended effect ( even though the losing side remain embittered). The country didnt fall apart either. The politics remains polarized but that would be the case with or without intervention.
I agree that regional countries/orgs would be preferable if possible - they usually have more "skin" in the game. But you overlooked the examples of clear Western intervention in Africa that worked out moderately well ( British intervention in Sierra Leone to keep fragile elected government in power) as well as France's role in the intervention against Gbagbo that ended a political deadlock in that country and has so far put it in the path towards recovery. In all examples residual political polarization remains, but the interventions overall led to a turn for the better.
The problem is we can name many other interventions / regime change done by or heavily influenced by the U.S. and the West that had negative results. Liberia, Congo-Kinshasa, Libya (the most recent one). Liberia resulted in a long, long conflict. Congo-Kinshasa resulted in Mobutu being in power. We all know what happened in Libya. Those are just the ones on top of my head.
Yes, there have been some interventions by the west that produced some positive results, or at least very little negative results. Problem is when interventions go bad, they often go very bad and for a long time.
In Libya's case, we now have a failed state and an intervention/regime change that has long-lasting negative consequences for Africa, Europe, and the Middle East directly. Add the fact that this occurred not even 8 years ago and that it comes not long after Iraq and it'll rightfully overshadow positive interventions by the west for a long, long time.
Another thought - why is it only American intervention that leads to outpouring and very strong reactions? You mention Syria, but I think its pretty clear that the most significant direct American intervention there was direct towards ISIS and not the regime. Syria is a perfect example of what I mean. Russia and Iran directly intervened there, have contributed thousands of soldiers, foreign militia, military hardware, and airstrikes towards maintaining Assad - yet few in the anti-war/left even spoke of this as an intervention? Cant have it both ways.
America has a rep for interventions. It's been doing it for decades all over the world with often costly results for citizens of said countries and even US troops.
As for Syria, the U.S, Saudi Arabia and others were indirectly--and sometimes directly--trying to depose Assad. The U.S. in particular was in favor of Assad being out and made that quite clear. Meanwhile, Russia and Iran, neighbors of Syria with long ties with the Syrian government and the Assad family, were requested by Assad to step in, long after the war already started.
One side wants the local government gone, while the other sided with the local government, at the local government's behest. Add the fact that the war in Syria resulted in similar results like Libya for a while and thus many people don't consider Russia and Iran's actions the same as recent US interventions.
Biggest difference between Libya and Syria is that Russia and Iran prevented the Assad government from collapsing. If the opposite occurred, there's a possibility Syria could've turned into another Libya.