I think you are downplaying what Matthew looked like it could do a couple days out.
The effects 60-70 miles west of the center of Irma are going to be similar to the effects 60-70 miles of Matthew. San Juan Puerto Rico got within 50 miles of the center of the storm and never saw hurricane force winds.
If the storm takes a similar path relative to Orlando that Matthew took (and that's what the current track shows) then I think that's pretty reasonable.
If the storm makes a landfall, even for just a few hours down in south Florida near Miami (God help them) then the storm might be even weaker than Matthew was when it passes east of WDW 12 hours later.