Multiple independent sources confirm that the All-In Summit 2024 was held as an in-person, three-day event at Royce Hall, UCLA in Los Angeles from September 8–10, 2024, with a large paid audience. The All-In podcast’s own Wikipedia entry notes that the 2024 summit "returned to Royce Hall from September 8 to 10" and drew about 1,950 attendees. (en.wikipedia.org) Hotel and event listings (e.g., BAE Ventures and several Marriott-affiliated event pages) also describe All-In Summit 2024 as a physical event at Royce Hall on September 8–10, 2024. (baeventures.com)

Since the summit did in fact occur in Los Angeles on those dates with in-person attendees and was not canceled or made fully virtual, Jason’s prediction was accurate.