This is missing two very important things: discounts and ticket cost.
Discounts: In all the times we have been to Disney World, there was never once a time when there was not a discount available at most (if not all) Disney hotels--the most we have ever paid for Beach Club was a little over $400 a night. If you're paying the rack rates of $600+ a night, you're doing it wrong. In contrast, we've priced out Universal a few times and while they sometimes have discounts, it typically requires a longer stay and but with only two parks compared to four at WDW, a longer trip to Universal doesn't really make sense to us. For the two-night stay in the below example, the best available discount was a whopping $10 off, total.
Park tickets: Especially if you go for shorter trips, these are also considerably cheaper at WDW. If you are going for a longer trip, Tickets may be cheaper at Universal with available discounts again, but again, often for longer stays.
Example: we were considering weekend getaway, Friday-Sunday, family of 5. We like deluxe hotels so are comparing Premier at Universal to Deluxe at WDW. Total price for 2 adults, 3 kids, a standard room, 2-nights, 2 day 1 park per day tickets, for the lowest cost Premier and Deluxe options respectively were:
Royal Pacific: $2,551
Yacht Club: $2,380
We also have to pay the cost of airport transportation at Universal, which is $200 round trip at Universal if we use their shuttle (we can't use Uber given we need 3 carseats, and a rental with 3 carseats is more than the shuttle cost). Recognize Disney is doing away with the free shuttle next year which may make Universal a better value for us, but for this year that increases the price difference to close to $400 more at universal for the same trip. And we also have to have one of the kids sleep in a rollaway bed at Universal, which is less than ideal and makes a small room even more cramped. Not to mention that most of the rides at Universal have height limits that mean I can't go on them with my kids.
So bottom line, you can't make a blanket statement that Disney is always more expensive than Universal for a comparable stay. Yes, it may be that Disney is more expensive based on the way YOU prefer to do your vacations, but that doesn't apply to me or others who have different vacation styles and needs.
This reminds me of the debate over the dining plan. I have to roll my eyes at the people who say it is "impossible" to save money on the dining plan unless you order food you don't want. That's never been the case for us, and we always came out significantly ahead on the plan eating exactly where we wanted to, ordering exactly what we wanted to. For resorts, like with the dining plan, you really have to do the math and can't just assume one will be more expensive than the other.