I think the difference between a classic “studio” park and the modern immersive IP park is fairly clear - a studio park offers the “illusion” of going “behind-the-scenes.” In this way it’s pseudo-educational, somewhat reminiscent of classic EPCOT (not surprisingly, MGM grew out of a planned classic EPCOT pavilion). In tourist studies terms, it offers staged authenticity, a pseudo-backstage, presenting the filmic IPs as explicitly unreal as part of a larger claim of behind-the-scenes realism. The modern IP park, made dominant by Uni’s own Potter lands, dispenses with the behind-the-scenes pretense and treats the world of the IP as absolutely real, taking that realism to extreme lengths.
The elements at Uni that still evoke a “behind-the-scenes” studio aesthetic are remnants of an earlier version of the park - Finnegans, Horror Make-Up, Animal Actors ET, etc. (they’re also some of my very favorite elements of the resort and I hope they remain for a very long time). Those are all opening day or close to it.
The only remaining later addition that pushes any kind of “behind-the-scenes” element is Mummy, which is actually a brilliantly illustrative transitional case - the entire attraction, from queue to unload, is stuck in a confused push-pull between whether it’s “authentic” or behind the scenes, reflecting the confusion surrounding the changes to the parks direction taking place when the ride was being planned and built in the early 2000s. MiB is also part of this transitional period, highlighting and satirizing the “behind-the-scenes” conceit.
Since then, the park has left the “studio” element far behind, with attractions like Bourne going to absurd lengths to create a storyline to make the attraction “real.” New York is no longer a New-York-themed backlot, it’s just New York. Even Fallon isn’t “behind-the-scenes” ala a studio park - guests are a front-of-house audience offered no special access and the attraction abandons the studio at the first opportunity.
So no, Universal Orlando is not in any meaningful way still a classic studio park.