What would collective acts of grief look like? Entire processions marching in black? Vigils for those that died of covid? Twitter bots listing their bios and faces for each victim.
We can write entire books on the victims of 9/11 but we have the equivalent of 1 9/11 in victims every month or so and we shrug our shoulders.
I'm not going to shit on this person, I will say that mass death is nothing unusual from a historical perspective.
People view genocides and programmes like the Holocaust as aberrations, but historically and to this day there's always been groups of people getting completely fucked and massacred in some way or another.
Mourning the dead is necessary, obviously, but humans generally haven't directly grieved the loss of people who aren't close to them or otherwise impactful in their lives. Knowing about abstract suffering or avoidable death will certainly affect different people in different ways, but I don't think we evolved to be greatly affected by deaths in a remote tribe, which is effectively anyone outside of your social circle for all intents and purposes. We might inform future communal decision-making, governance, policy, resources toward learning from avoidable mass casualties. Maybe, even that low bar is hard to clear nowadays.