There may be many advantages to small teams and yes there are cases where they have wild financial success, but in general these may just be outliers. Are these outliers because they have the secret sauce worth emulating? Maybe, and maybe their stories will show why they succeeded where so many failed. Success is rarely all luck, but we’ll likely also invent myths around their exceptionalism as we tend to do. Not the type of exceptionalism which precludes the rest of us from having a similar shot of course, but one about cleverness and grit or other characteristics we can fairly easily attribute to ourselves.
Everyone likes a good narrative, I suppose. And narratives about scrappy small teams achieving success meritoriously are more attractive than ones about how the massive organizations usually tend to eat them for lunch (despite having their own types of problems) or ones about the frequencies with which the scrappy teams fail. Cherry-picking data points is the key to any good narrative.