If BTC breaks $500k, that's probably the only time that I'll have money to invest in Space X. I've invested mostly to bitcoin and I don't know yet my next plans of reinvesting it to another asset. Space journey might be interesting in the next 5 years and the market cap of bitcoin will continue grow at that pace as well. All I can say that there's still a lot of things that can happen within that period and I don't mind if Space X reaches first to $1k than bitcoin's $500k. Both are valuable asset right now but I have my bias since I don't hold SpaceX.
The question for you will be "By the time BTC reaches $500,000, will the price of SPCX shares still be attractive for you to buy." Let's say for example if Bitcoin goes up to $500,000 and the price of SPCX goes let's say $1000 or maybe $1500. Will you still buy? Will you sell your Bitcoins just for buying SPCX? Will you still think that SPCX is still undervalued during that time then?
That is right, I don't know if the price by that time is still attractive to invest for the SPCX. I would like to diversify by that time but, it won't be sure if I still want to invest by that time. But if it's about variation of investments, it's desirable but that changes over the period of time.
Not many know it, but SpaceX is just riding the wave of AI, and there are many videos that can prove it. I just can't remember how it became a company that belongs to the AI sector but for sure, SpaceX is more of an AI-related company which for me is a big no-no because I believe that the AI industry has hyped too much that it's currently in the bubble, and it's only a matter of when until it pops.
IIRC, there's an acquisition that happened which has made it a part of the Grok creators. And right now, grok(AI) has been used in many things especially for the X and Tesla cars. So, since all of these products are from Elon's then that's how it became an ai company. But I agree with you that AI's hype is massive right now, if it's on the peak then it will calm down soon. As we all know, "everything that goes up must come down".
Like you though, I also choose to go and buy Bitcoin and crypto rather than SPCX. I'm not a fan of shares that don't give dividends anyway.

The dividends is what makes me interested if I'm about to diversify into other assets or stocks but, I don't know yet because gains from bitcoin is massive than them as per experience through my holdings.