Airbnb stock trades below the closing price on its first day of trading in December 2020.Long-term holders of Airbnb (ABNB 0.68%) stock have likely experienced deep frustration with this stock. Due to the site's ability to increase the supply of vacation properties, attract new landlords and tenants through the popularity of its brand, and apply artificial intelligence (AI) to solve business-related issues, many investors thought it could achieve outsize gains.Amid that optimism, it debuted in late 2020 at ...