There is no should or should not.

Look at the financials and the price, and you as an individual get to determine if it's worth buying (or selling).

What do you mean by this? The person you responded to never used the words "should" or "should not", and then you basically repeated what they said using more neutral words...

What is so controversial about saying that SpaceX seems overpriced?

His point is that sellers can do whatever suits their interests best, they don't have a duty to pick a fair price. And that it's on the buyer to decide whether to accept it or reject the price.

Duh? That point was actually implied by my initial comment.

Nobody said anything about fairness or duty.

My point was that if the seller is trying to maximize its self-interest by maximizing the IPO price, leaving no room for growth after IPO, then buyers probably want to take a pass at that price.