Sources report that the US Center for Disease Control (CDC) has extended its requirement to wear masks on public transportation by 15 days. People riding on planes and public transportation will need to wear masks until May 3, although the original travel mask requirement was set to expire on April 18, 2022.
Historically, Disney has followed CDC travel mask requirements on its monorails and buses, so it is likely that Disney guests on monorails and buses will need to wear masks for a while longer.
Currently, masks are optional for fully-vaccinated Walt Disney World guests on the Disney Skyliner as well as other indoor and outdoor locations.
Will you visit Disney World before April 18?

