How can it be that none of Israel’s direct neighbors (Syria/Lebanon in particular) never, I mean over decades seemingly, ever seem to have any air defense systems - even old soviet ones that at least fire and miss the target?

We have that situation, and at the same time the cognitive dissonance of seemingly the entirety of the alternative commentariat (and beyond) with one voice having said that If Israel attacks Lebanon Israel is finished. It may very well be finished, but if so, it will probably have to be death by a thousand cuts at a huge price for everyone.

As for the Russian ambassador - what proportion of Israeli citizens are also Russian citizens? China, apart from wanting to be a neutral arbiter, would indeed seem to have a free hand to withdraw its amabassador, its a good point.