I forgot Pirates and PhilharMagic only has Coco from this century. Country Bears has modern songs now but not modern characters.
MK does always seem to be 20 years behind, New Fantasyland used film that came out then 20 years ago. Completely understand that Cars might not fit in Frontierland, but MK does need some IP injection from the last 20 years, particularly from the New Renaissance era of Disney (Princess and the Frog to Encanto)
If they are created this century or altered..they are of this century in production. I see your IP point though.
New Fantasyland is the opposite problem and only happened because DIsney's goals for the remakes were in affect. No coincidence the anchors included Beauty and the Beast, Dumbo and Mermaid. While the attractions are based on the classics, the international recognition and synergy was there. The slate was ready to begin for all the majors to be remade.
MK only seems 20 years behind because management for 20 years plus now has been terrible.