The next episode after E16 is E17, “Big Tech bans Trump, ramifications for the First Amendment & the open Internet,” released on January 11, 2021, three days after E16 on January 8, 2021.(allinpodcastsummary.com)

Between those dates, at least one event clearly fits “highly unexpected and highly impactful”:

• On January 8, 2021, Twitter permanently suspended Donald Trump’s @realDonaldTrump account, an unprecedented move against a sitting (then-outgoing) U.S. president and a major shift in platform governance. Multiple outlets documented this as a permanent ban due to the risk of further incitement of violence.(theguardian.com)
• In the same window, Amazon Web Services cut off hosting for Parler, and the site went offline on January 11, 2021, after Apple and Google had already removed its app—another major, widely covered escalation in Big Tech’s moderation response to the Capitol riot.(techcrunch.com)

E17 itself is devoted to discussing these bans, which the hosts treat as a major, consequential development.(allinpodcastsummary.com) Given that at least one such event (Trump’s permanent Twitter ban, plus the coordinated deplatforming of Parler) occurred between E16 and the next recording/release, Friedberg’s prediction that “some highly unexpected and highly impactful thing will occur” before they next met was borne out.