Elon Musk mocked ULA's 2015 doubts on reusable rockets as SpaceX's Falcon 9 set records this week: its 400th drone ship landing and Booster 1067 completing a historic 30th flight since 2021. While ULA's Vulcan flew only twice this year, SpaceX has launched 73 times. Retail sentiment on Stocktwits leaned bullish on Rocket Lab ($RKLB).