There's a real desire out there to tell a narrative where SpaceX is a massively fraudulent piece of financial engineering, a pump and dump scam where the stock will "collapse within a year" and retail investors will be left holding the bag.

There's definitely some financial engineering at the margins, but as I see it the facts are:

- Musk is still going to own 40% of the company. If he's selling 4% of it, his incentives are aligned with keeping the rest of it high

- the index funds ultimately are fast tracking the big IPOs because their customers, in aggregate, want that. And the market structure really has changed since the days when the index inclusion rules were first written and companies went public smaller.

- People have been banging the same drum about short sellers with Tesla since at least 2017 - AFAIK it's still one of the most shorted stocks - and it's up 20x since then.

- Institutional investors with more sophisticated strategies than "buy the index" or "pump and dump lol sell to the index funds" will be participating in the IPO and in fact will be the main drivers of price. Everything I've seen suggests that if this is a "retail heavy" IPO, that means 20 or 30% of the shares ending up with retail instead of a more typical 10. These other institutions could be wrong, but they're not mechanical price takers.

I've shown above how one of the effects people make the most noise about - the index balancing arbitrage - is likely an effect of order of magnitude 1%. It's on the noisemakers to show how any of the other effects you mention can be massively more impactful.