Apple has a float of >99%. SpaceX is going to come out with 3-4% float. Since all big serious total market / whatever index funds are float adjusted, this means that SpaceX will be treated more like a company with $45B market cap, not $1.5T or whatever.
If you're buying most index funds, you should literally not care about this.
If you buy VTI, then SpaceX is going to be like what, <0.1% of the fund? That is noise.