I think a big part of Potter's cultural impact as a park has less to do with the branding and more to do with the immersion offered up by Universal.
That's not to say that the brand itself wasn't a hugely important factor to it's success, but I think it's easy to forget that before Potter, the idea of a massive line for theme park gift shops was a pure dream for any theme park executive. The brand lended itself very well to this, because between the world building of the books and the iconography of the films, there was just a super strong concept for a place that enveloped you, and I don't believe theme park lands had really achieved anything that encompassing before.
You can to this day, go to the parks, buy the entire costume of a Hogwarts student, and then proceed to spend the day in Hogsmeade as though you were living that reality. It was and continues to be one of the biggest wish fulfilment creations for any franchise anywhere. There's no Coke in the Wizarding World, no random theme park merch - everything therein is part of the world, down to what you touch, smell, hear and purchase.
It's also part of the novelty and the intrigue that the land generated. People who had little to no knowledge of Potter were aware of the fact that this was a place you could get lost in, and that made a lot of people at the time very interested in what it was all about at Universal.
Pokemon has many opportunities to do similar things with individual experiences, but it lacks an iconic, cohesive environmental identity that immediately reads for every fan of the franchise as THE place you want to go experience within that world. That factor combined with the fact that people have become accustomed to the hyper immersion concept makes it a lot less likely that random people want to go see it because they're curious about exactly how encompassing it is, because this is no longer a novelty to anyone familiar with the theme park landscape.
That doesn't mean it won't make bank, and it doesn't mean that it couldn't potentially trigger another unexpectedly large success upon opening. But Potter still feels very much like lightning in a bottle as a cultural moment that redefined what theme parks can be for the general public, and I'm not sure any franchise could recreate it at this point in time. I think that would require some kind of innovation that no one has dreamed up yet.