I'm thinking you are wrong. There are definate quotes saying Epcot wasn't about rollercoasters.
Two distinctions;Walter Elias Disney operated under the belief that EPCOT center would be a fully functional utopia-like city. The Florida property was so big because of that, with the plan to fill it all with the city of tomorrow. Never in his lifetime was EPCOT as a theme park the prevaling idea. Sure, you're probably right in saying that there are quotes where he talks about EPCOT center not being about roller coasters, but this was his city, not the permanent world's fair that WED/WDI designed after his passing. He can't have commented on a project that didn't start until well after his death.
E.P.C.O.T. was Walt’s City
EPCOT Center was not Walt’s city. That name evolved around 1974-5.