Assessment window
Sacks was speaking on June 20, 2020, and explicitly said the picture could be very different in “five [to] six months,” i.e., roughly November–December 2020—right around the 2020 election.

What actually happened by November–December 2020

1. Election outcome
   By November 3, 2020, Donald Trump’s political position did not become more favorable; he lost reelection. Joe Biden won 306 electoral votes to Trump’s 232 and won the national popular vote 51.3% to 46.8% (a 4.5‑point margin). (en.wikipedia.org) A president who loses both the Electoral College and the popular vote is not in a “significantly more favorable” political situation than when he was already viewed as vulnerable.

2. Polling: June 2020 vs. late October/early November 2020
   National head‑to‑head polling between Biden and Trump in May–June 2020 generally showed Biden leading by high single‑ to low double‑digit margins (often around Biden +8–9). (en.wikipedia.org)
   Aggregated national polls in the final week before the election still showed Biden ahead by roughly 7–8 points on average (e.g., 51–52% Biden vs. 43–44% Trump). (en.wikipedia.org) The race tightened somewhat in the final result (Biden +4.5) but Trump never moved into a clearly favorable or leading position nationally. The overall political picture for Trump in late October/early November was broadly similar—still trailing by a sizable margin.

3. Trump’s job approval
   Trump’s job approval did rebound somewhat from early‑June lows but remained underwater. Gallup shows:

   • June 8–30, 2020: 38% approve, 57% disapprove.
   • Oct. 16–27, 2020: 46% approve, 52% disapprove.
   • Nov. 5–19, 2020: 43% approve, 55% disapprove. (news.gallup.com)
     So while there was a modest recovery from June, by the election his approval was still clearly net negative—historically a bad place for an incumbent and not consistent with the idea that his political situation had become significantly more favorable.

4. Economy and unrest (the mechanism he cited)
   Economy: The unemployment rate did improve dramatically from the worst of the COVID shock—falling from about 13.0% in June 2020 to 8.8% in September and 6.7% in December 2020, indicating a substantial partial recovery. (ycharts.com)
   Civil unrest: The most intense nationwide George Floyd protests were in late May and June; large‑scale unrest did subside somewhat by late 2020, though political and racial tensions remained high. This means the conditions Sacks expected (economic rebound and reduced unrest) partially materialized, but they did not produce the dramatic political turnaround he predicted.

Conclusion
Sacks’ core claim was that Trump’s political situation in the 2020 election would look “very different” and more favorable within five to six months. By that time, Trump still had negative net approval, continued to trail Biden by substantial margins in national polling, and then lost both the popular vote and the Electoral College. Even though the economy partially recovered and unrest eased relative to June, Trump’s reelection prospects did not become significantly better.

Verdict: the prediction was wrong.