From a practical matter, Russia is very influential in these parts of the world. With Russia basically controlling Syria, we cannot get on Russia's bad side, especially when we need their silent acquiescence to act in Syria and Lebanon against Iranian interests. That plus Russia being a big and powerful country with some sort of relationship that we want to keep.. Those are the practicals, but I do not think that is the main reason.

On the one hand, Russia is being an aggressor and invading the much smaller Ukraine and there is little Ukraine can do about it. And the reasons are not well understood by anybody. Russia is breaking agreements along the way, and the West not coming to Ukraine's defense makes Russia just look like an aggressive bully rolling over the little shrimp. So everyone wants to criticize Russia because they come off really bad here. If Putin cared at all about what other people think he would have started with a great marketing and public relations campaign to explain why this is justified, but he didnt, so he just looks like an aggressive bully.

On the other hand, we are Israel. We get accused of almost the exact same thing, though the circumstances are different and the world response is different, but my theory is that in the Middle East most of the world sees Israel as an aggressor having "invaded" Palestine, in some way, and taken land for themselves from a smaller and weaker group of people. I think that many Israelis and maybe the government feel uncomfortable criticizing Russia for something very similar to what the world criticizes Israel for, even if the circumstances are different.

(Why the world does not take moves against Russia the way it does against Israel is a different discussion)