A new exhibit at Boston’s Museum of Fine Arts has ostensibly been put together to show off the impressive collections of William I. Koch. But as it turns out, the collector himself is the real star of the show, his outsized personality dominating the art he has amassed over a lifetime of collecting. “Over the years, Koch has skippered an America’s Cup winner, built a billion-dollar energy company, sued his family members, engaged in a high-profile court battle with his onetime mistress, and been arrested for allegedly beating his then-wife. (The charges were later dropped.) He’s also built an art collection that has attracted the attention of countless museums.”