I know nothing about stocks, but what are the lockups you mentioned?
The lockup timing for SPCX is staggered, and should be where the stock will drop because of more shares becoming available to trade, after 30 days, 180 days etc.,
It prohibits insiders (Elon and pals) from selling shares for a set time to allow for price discovery and stabilization, where a sudden large supply would cause the share price to drop more than normal. It prevents inside knowledge from cashing out right after a company goes public, with some small assurance at least for the long haul.
Early investors have waited a long time to recoup gains, they deserve to benefit, just not immediately after it goes public until certain conditions are met.