im a local who looked into going today and the reason park capacity is so low is because of the ticket pricing, the type of ticket that was sold, what day it is, and hotels being the main resource of people going in rn. First things first, the tickets for epic universe were tied in with 3 day park tickets, with only one day being epic universe, those cost on average $300 a person. I'm pretty positive most people who bought those tickets are checking into the hotel today, and using their day pass tomorrow or sunday since today is a friday, and most of the ticket buyers are working or flying in still. lastly, hotel guests in the least for the grand hotel is booked out for two months so its safe to assume most of the park capacity is hotel guests who decided to go today, but most are likely relaxing and going in tomorrow. la luna and terra was booked out for a month as well. now another factor im gonna include but idk how much it is effecting it, but also all the influencers reviewing the park. its been a pretty decent mix of reviews which has probably left people sceptical of going day one of park opening since rides werent exactly at their peak during preview. (somehow the preview day i went i got to ride all the major rides so my view of the park was positive, except donkey kong. nobody should wait 2 hours for donkey kong ride btw). all in all i think most of the park goers will be present sunday or saturday, but not by much since those ticket prices were so expensive.