Maybe Nasdaq shouldn't put Space X in the Nasdaq-100 index fund 15 trading days later vs six months.

Nasdaq is a company that exists to make money.

They make money by curating an index i.e. a list of companies and licensing that list to other companies for a fee.

If they pick good, profitable companies with great future, then the business continues. If not, the business fails.

So when you're debating "should/shouldn't", the only perspective is that of Nasdaq, the company, and they only question they "should" be interested in is: is SpaceX a good company with great feature that will make the list better.

The 6 month rule was created by Nasdaq, the company, in order to pick good companies. It's not a religion. It's not a suicide pact.

Therefore when faced with historic IPO (the largest IPO ever) it's a sign of good management that they are not applying the same rules to SpaceX (debuting at $1.75 Trillion) as they do to companies that IPO at $100 million.