The accuracy problem is resolution. A model built on postal-code or watershed-level data cannot see a specific lot's grading, a nearby drainage improvement or a basement's actual waterproofing, all of which change real risk more than a generic score does.
That does not make the scores useless, since they are a reasonable first flag for insurance shopping or a conversation with a lender, especially on property near the South Saskatchewan River. It does mean the number should prompt a proper home inspection, typically $400 to $600, rather than stand in for one.
Treat a climate risk score as a starting point, not a verdict on a specific property, and confirm anything material with the City of Saskatoon before it changes how you price a home near the river. Get your hand-reviewed valuation from Joel Dyck.