Dreams aside, this story is court politics: "Transportation Secretary Sean Duffy, who is NASA’s acting administrator, has told people that he wants to lead the space agency" [2]. "So does Jared Isaacman—the billionaire entrepreneur who was the nominee earlier this year before President Trump withdrew his support."
With "both men...jockeying to lead NASA," and, just "this past weekend, advisers and lawmakers representing Duffy and Isaacman [having] called contacts in the Trump administration—including the president himself," this announcement is politics through PR.
Duffy may threatening Elon to have his man back down. He may be going scorched Earth, signalling to Trump that Musk's decision making isn't to be trusted.
[1] https://opsjournal.org/DocumentLibrary/Uploads/The_Lunar_Spa... 2017; 2bn US2017 ~ 2.6bn US2025
[2] https://www.wsj.com/politics/policy/trump-nasa-administrator...