I think it is ridiculous that there is ever lines drawn in the sand over this. I've seen it here, people who are WDW lifers that won't take one year off and go to Disneyland. I've also talked to a few who are Disneyland locals that don't want to visit WDW until they see that they have cleaned it up better. Meanwhile...........they have never been there and seen the beauty or grandness of it to judge themselves.
It is crazy. Do both. Honestly, there are enough people on here who have gone to both as well that can back me up on this. You are missing out big time if you don't experience both of them. What do people complain about on here? How Magic Kingdom has lost some of their dark rides. Disneyland has them! Snow White, Mr. Toad, Pinocchio, Alice in Wonderland are all there and they are Fantasyland dark rides MK doesn't have anymore, or in some cases never did. You can ride Casey Jr. at Disneyland. Or the Matterhorn, or Indy. Or have a longer Pirates ride and one of the last things Walt ever approved before he died.
MK has the Carousel of Progress and obviously Hall of Presidents is done on a more grand scale than Mr. Lincoln. Country Bear Jamboree is still there and a better version of Splash Mountain. A bigger castle and more space and if you don't like that, then go to the other three parks or explore the resorts. Take a boat ride from Disney Springs to one of the resorts. Heck, stay on the boat all day if you want, it's free. Go visit Epcot, there is not another place like that in the entire world, very unique.
That's the beauty of it, both parks and resorts have something the other doesn't. I'll take Disneyland as the best individual park because it is the original and still has a standard no others have. It is hard to beat. But please, don't turn your nose up at the other side of the coast because you are missing out.