Eh.. their maintenance is top notch and they do a wonderful job of preserving the attractions there, but they actually are pretty modest in their investments.
BATB is the first major addition to the park since Monsters Inc in 2009 and before that was Pooh's Hunny Hunt in 2000.
I mean, Tokyo DisneySea within the span of the decade after Monster's Inc did bring large scale investments.
Especially with versions of Toy Story Mania and Soarin, alongside the redo of Stormrider to Finding Nemo/Dory. And even then, those were rather big additions for the land they were on.