I think it’s complicated. No, I don’t think the park is being review bombed any more than Volcano Bay was review bombed. There are plenty of guests frustrated with their experience.
But keep in mind who leaves reviews on Trip Advisor in general and who leaves them on a new theme park in specific. That’s under 1,000 reviews, which is not a lot for a major theme park.
I think Epic is the worst of the non-SeaWorld parks in Orlando, and frankly I don’t think it’s that close. But obviously a) your mileage may vary b) the park is only half a year old and c) you can’t currently go to the park in the same bundled way you can go to the existing parks. That à la carte method certainly changes how critical someone is of their experience; or at least, I’m sure it affected my opinion.