I don't have anything to say about their concentration beyond that if you read their early 13Fs (ex https://13f.info/13f/000204572425000006-situational-awarenes...) they were in fact "that concentrated" which is why it's plausible they got 100s of % returns without leverage. Re options being leverage - everything you said is true but unfortunately the public filings dont have strikes or durations so it's not possible to say whether they bought short dated otms with 0.05 delta or leaps with close to 1 delta or something in between.