Rabbi Jonathan Saks: Commentary to Tashlikh from pp. 936-947 of Koren-Sacks Machzor for Rosh HaShana
It is a custom, on the afternoon of the first day of Rosh HaShana (or second, if the first is Shabbat) to go to the shore of the sea, the bank of a river, or other running stream of water, as a symbolic enactment of the words of the prophet Micah: "He God] will cast (tashlikh) into the depths of the sea all their sins" (Micah 7:19)...The first mention of the custom is in Sefer Maharil of Rabbi Jacob Moellin (d. 1425)...Many folk customs have become associated with Tashlikh, among them the custom of throwing crumbs into water as a symbolic gesture to accompany the process of repentance, begun on Rosh HaShana, as if we were "casting away" our sins. This practice was dismissed by some halakhic authorities and ridiculed by gentiles.

1. Why do you think Tashlich was dismissed and ridiculed?

2. What does Tashlich and or repentance mean to you?

We’ve all seen performative and insincere allyship in the days since George Floyd died in police custody, and some of us may come at something like this with some degree of skepticism.
I think it’s great that people want a visual uniting symbol of solidarity, but I can also see how people who haven’t said a word in the past — or in the past week — feel like they’ll look bad to their followers if they don’t post. So they post, but with no real intention of listening, learning, donating, protesting or helping beyond the post. The post makes them feel like they’ve done their part.

When Did Instagram Go Dark?
We have mixed feelings about #BlackoutTuesday, too: https://www.nytimes.com/2020/06/02/style/instagram-blackout.html

Modern thought has a tendency to extenuate personal responsibility. Understanding the complexity of human nature, the interrelationship of individual and society, of consciousness and the subconscious, we find it difficult to isolate the deed from the circumstances in which it was done. . . Yet this general tendency, for all its important correctives and insights, has often had the effect of obscuring our essential vision, aiding our conscience to grow scales: excuses, pretense, self pity. The sense of guilt may disappear; no crime is absolute, no sin devoid of apology. Within the limits of the human mind, relativity may be true and merciful. Yet the mind’s scope embraces but a fragment of society, a few instants of history; it thinks of what has happened, it is unable to imagine what might have happened. The qualms of my conscience are easily cured–even while the agony for which I am accountable continues unabated.

3. So what is Heschel saying here?