Call me skeptical. This is a Doug's Ferris wheel project. Assuming that the City powers-that-be don't try to muscle out Waterfront Toronto, the flood protection could be done as per WT and we could end up with their vision. But it's just as likely that some bright light will say "well, we don't have to protect X, Y, or Z, just the World's Fair site" and take money better spent elsewhere to build a 'temporary' berm to protect the temporary structures.
If we took all the dollars that would be spent on the World's Fair and the Gardiner re-build, and used them to fund WT's plans, we could have a developable soap plant site, a developable Portlands, the spillway/parklands would be in place, and the east end of downtown would be a thriving business/commercial/retail/housing community for the benefit of all Toronto. Or we could have a really big version of the Ex.