To put this in perspective, over 150 thousand people die every day. About 2 die every second. You can't mourn them all, and you'd probably get severe depression if you genuinely tried your best.
I'd guess the point is that saying that a tragic event takes away some 'accomplished' people appears to diminish the loss of the unaccomplished people. So the statement would refer to all people lost in that tragic event, not that we should consider all people when one/few die...
But conversely, if you mourn only the people lost in that tragic event, doesn't that diminish the loss of people who die in no less tragic events that don't get publicity? (which is the vast majority of them).
My point was that it's all cherry picking, because you can't mourn everybody, and we don't even try. Draw a line far enough, and beyond that death and suffering is all very abstract, even if we do know about it. And mostly we do not - although we know where to go if we wanted to find out, we don't want to find out; events of comparable magnitude and depravity happen in some areas of the world with far more regularity.
So it feels a tad hypocritical to focus on this particular way to cherry pick as disrespectful.
I agree, I only refer to when a particular event is noted (cherry-picked by the media) that we don't call out the 'smarter' people as a greater loss within that context.