Since California Adventure will be demolishing the entire A Bug's Land themed area by this summer to make the upcoming Marvel-themed are in 2020, I do got a feeling that they might do the same thing to Mickey's Toontown by the 2020s decade.
Like the recently closed It's Tough to Be a Bug! entrance at A Bug's Land, the land has suffered from damages that they are not bothering to fix at all (most notably the cardboard cartoon mountains), which got me the feeling that they will demolish the land to make either its own Fantasyland expansion (like what they did to Mickey's Toontown Fair at Disney World), a Frozen Land, or its own Storybook Circus themed area.
If this does happen by the next decade, we will miss and remember the land.