"idealized notion" is a correct and usable phrase in written English.
You can use it to refer to a concept of perfection that is not based in reality. For example, "The idealized notion of a perfect family is unrealistic, as no family is perfect."
When I first moved to Rome, I had this idealized notion of the city.
That's the idealized notion the families have about the purpose they serve.
But in the suburbs, which are themselves built around an idealized notion of family life, absence is never far from mind.
Even when we ask candidates directly about EI or EI-related competencies, they talk about an idealized notion of themselves and what they'd like to be, rather than how they really behave.
I had a clear, if idealized, notion of my requirements: a thatched-roof cottage in a sleepy English village; a rustic stone fence bordering pastures and meadows; honeysuckle and roses by the front door; a pub just a short walk down the lane, and easy access to London should all the above ever become boring.
Taken together, these principles deliver a highly idealized notion of knowledge (belief), not mirroring the actual status of human, that is, finite and fallible, epistemic agents.
Boomers have long idealized the notion of working for 30-40 years behind a desk for someone else, relegating retirement and the freedom to travel to the "golden years" of life.
This is not the way it is supposed to be in nation that idealizes the notion that any child can rise from modest circumstances to greatness.
First, LaPierre made a passionate rebuke to the notion, idealized by some, that all gun owners are evil.
Distant fathers are idealized fathers; idealized fathers are distant fathers.
Native lands, the places where California Indian tribes had interacted closely with the landscape for generations, were designated as unpopulated "wilderness" areas to conform to Euro-American notions of idealized, pristine conditions that supposedly existed before contact.
