Sounds like the standard liberal idealist idea of just vaguely gesturing the collective will and vibe of the people without putting any kind of force behind it, therefore rendering it as a simple vent release for societal unrest and dissatisfaction, intentionally so or not.

The only real way I can think of off the top of my head to turn collective acts of grief into something productive, would be to funnel it into a general strike or at least any kind of strikes, people were in essence murdered by the state and the bourgeoise in order to keep the economy and profits flowing, its time to sabotage that system and get justice for all those we've lost etc.

Like "They dont want you to grieve the victims of covid or climate change", even if you did what would that change? Okay we're all grieving now but society is structured the same still and the state and politicians have no process for the voters to hold them accountable, so any and all promises offered from this collective grieving will be broken and torn away when convenient.