This is obvious. The hypocrisy in us is so strong that we try to use any excuse to appear better. Example: relatively recently, the world was sad because of some actor who died in an accident, but everyone forgot about the recently deceased Zhabotinsky, who, by the way, was, unlike the above-mentioned actor, our compatriot. This actor did not relate to us in any way, and Zhabotinsky set many records in weightlifting from the USSR.
In the modern world, to a certain extent, the statement "If some event is not reflected on the Internet, then it never happened", but this logic also works in the opposite direction: "Something is written on the Internet, then it is true" ... This gives people an easy way to show themselves better than they are. Hence, including the cult of selfies, ostentatious grief, ideological "struggle" in the comments
Two options - or posturing, or sincere empathy. It seems to me that there are not only hypocrites in the world, but also people who can really feel sorry for even a stranger. So I would not be in a hurry to attribute the herd instinct to absolutely all cases.
To simplify, this is a herd feeling plus the desire to be involved in something global. People might not care deeply about some Frenchmen and terrorists, but their friends started making avatars with the French flag. So it spread like fashion. The Fast and the Furious isn't exactly a cult movie. And very few people can name at least two more films with Paul Walker. However, you see the news of his death in the feeds of friends and communities, and thoughts come to mind "And I know this guy, as a child I watched him drive a car. Damn, I'm sorry for him." Although not really, social urges push me to write a tearful post. Or at least the reserved "r.i.p., brother".
All this great hypocrisy has not gone anywhere. We don't want to be considered heartless brutes who don't care about someone else's grief. At least the one that is heard.
For example, I myself could not resist and made a post on Instagram dedicated to Bowie. It looks like this instagram.com and, it seems, there is no pathos or feigned sympathy in it. Just a bow towards the bright person. Although, perhaps my internal copywriter did not let me miss the current news feed.
We live in a scary world.