I think you're wrong on multiple levels.
First of all, this is about empathy vs egotism. shaman is basically defending that it's okay for him to be egotistical because we were egotistical in other wars as well. The very fact that one side of this argument is actually supporting the victims is already evidence that they care about this stuff. So "by the same level of evidence" is already wrong. Those who care about victims are far more likely to care about them in other situations as well.
Secondly, even assuming we didn't care about other wars, there's a difference between ignorance out of a lack of knowledge ("it isn't in the media so I knew nothing about that war") and ignorance out of egotism ("I know they're suffering but the oil and gas prices are far to high, we have to consider our own interests"). In the first scenario, you could make the accusation that the individual in question didn't put in enough effort to inform himself, in the second scenario he/she knows how bad things are going but chooses their own interests anyway
Third, even if we genuinely didn't care for previous wars but now do, that is nothing one should be criticized for. You should criticize people for doing something morally wrong when they do it, not years after when they do the right thing. That's providing the completely wrong incentive and pretty cynical, even toxic.
And fourth (and this is why people are so annoyed by all this whataboutism, as this paragraph is actually offtopic again), none of the conflicts you mentioned is comparable to this one. With nuclear powers almost directly involved on both ends, a sovereign democracy under attack without any sort of at least somewhat understandable motivation behind it, deliberate and probably even ordered violations against the Geneva Comvention on an almost daily basis, the triggering of a global food crises and so forth.
