Anaheim is a very different beast. They need to market largely to local clientele. Far smaller pool of fresh guests. Therefore, lots of updates.
I'm not sure about the "There's always new things there" argument. We went in Summer of 2012. At the time, Carsland had just opened. We are going back next week. There's not much new in 4 years:
Two shows (Mickey and the Magical Map and the Frozen Sing-Along garbage)
Star Wars Launch Bay and Superhero HQ (yawn)
New nighttime parade and fireworks. (cool)
And they are just starting to work on Star Wars land - which is project to open 2018/2019.
Also Soarin 2.0 and new Frozen show coming.
In that same period from 2012 - 2019 - WDW will have opened:
NewFantasyland/Storybook Circus (3 rides/Enchanted tales/Be Our guest/ throw in Tangled Pottys)
Skippers Cantina
Festival of Fantasy Parade (If I'm giving DLR credit for a parade, I gotta give it to WDW.)
Frozen Forever / Soarin 2.0 / 3rd theater
Avatarland and Rivers of Light and Night Safari
Toy Story Land and Star Wars Land
Disney Springs re-do
So, I don't think DLR should be getting credits for "lots of updates" when WDW is doing much, much more nowadays.