I do like Universal a lot and they do some things better than Disney. However I do believe the overall vibe and feel of the place as a whole is not as classy as Disney. The clientele is generally younger and more rowdy, the employees are mostly on the younger side and while the service is fine, you won’t as frequently see ones who clearly love their job.
The food quality and options is nowhere near Disney’s level. For example Disney has all kinds of different snacks all over the park. At Universal your snack choices are almost always turkey leg, pretzel, or churro. Disney has endless table service options, many of which are amazing. Universal only has it’s chain restaurants in CityWalk.
Same with shows and live entertainment, characters to meet and interactions with them - Disney has significantly more and the quality just, for the most part, is several steps above any offering at Universal.
Disney has a greater variety of experiences. And though they may have less offerings for thrill seekers, you don’t get fatigue from experiencing the same type of attraction over and over.
Disney’s parks are more polished and clean. Things are always getting touched up, repainted, repaved, power washed, etc.. Much of Universal looks very worn and unattended like it hadn’t really received any care since it opened. Some areas of Universal do look amazing and WWoHP is up there with Disney’s best, but other areas, like much of USF, and Marvel, Seuss Landing, and Toon Lagoon look like grungy plastic and concrete tackiness.
CityWalk is okay but feels like a somewhat hodge podge of aesthetics and club atmosphere compared to Disney Springs which is now ridiculously upscale, almost too upscale.
I don’t think it’s fair to group UOR in the same class as Six Flags but they are still not on Disney’s level in many ways.