This is a little aggressive. The boring company is unproven technology in a perpetually capex heavy delivery model. If I was a spacex shareholder I’d probably value it at $0 in 2018, and strongly prefer it to be not associated with spacex at all.
If you want to sell your shares for 0$ that is up to you. On the flip side, I am happy to look through your personal holdings, and anything I think is worth $0, take for myself. You wouldnt mind now would you?