I'm pretty sure WDW is the largest single-site employer in Orange County, perhaps the entire state. If they do allow the station to be built, I think SunRail would want to provide service from all SunRail stations to WDW. It would seem foolhardy to build the line and not maximize ridership.
The issue from a commuting point of view is that the actual jobs at WDW are spread out so much.
In 2019, WDW had something like 70,000 employees, almost as many employees as work within walking distance SunRail stations in Downtown Orlando (80,000 employees split between two stations, for about 40,000 employees for each).
However, only Disney Springs will be within walking distance of the Disney Springs station. So that is probably only about 10-15,000 employees. It isn't nothing, that is similar to the number of people who work at MCO. But it is far less a draw than downtown Orlando. And there is a pretty heafty transfer penalty between train and bus to other Disney employment destinations. Not that nobody will do it, but it will be a niche service for commuting to the theme parks.