In this case we are assuming a 2 hour wait really matters that much. How would the troops have changed or escalated things? It looks like without invoking the insurrection act, the legal authority of the troops is limited to protecting the federal building and not policing the streets. Of course law has never stopped Trump. Newsom is suing, so we can assume there is a possibility of it being illegal..
It makes a nice diversion from trumps failing economy, tariffs, and the big beautiful bill, and is a show of political power. The practical functionality is in question.
Here's a comment form a legal authority.
...that for now the federalized troops appeared to have limited authority. Once deployed, they will be able to protect ICE agents and federal buildings against attacks by protesters but not to carry out immigration raids or police the city’s streets in general.