I doubt they’d need to go public. Regardless of your views on Elon, he’s consistently raised billions privately whenever needed. Even without Starship, SpaceX seems cash-flow positive and profitable thanks to Starlink and Falcon 9. It’s simpler to ask private investors to back his R&D efforts when they’re investing in an already profitable company excluding the R&D. Going public might echo Tesla’s early days, when profitability of the company as a whole wasn’t guaranteed.