The phrase "than supposed" is correct and usable in written English.
You can use it to compare one thing to another. For example: "The project took twice as long to complete than was supposed."
My point is that there's greater human variation than supposed.
Any Asian competitive threat surely comes more from the region's economic clout than supposed weaker rules.
"The Plautine in Plautus" consists in pervasive qualities rather than supposed innovations of plot or technique.
Research published last month now suggests the asymmetry could be far more substantial than supposed.
"The cure, that is the improvement of the body politic of the movie, is simpler than supposed, perfectly obvious. . . .
Research led by Christopher Gregg and Catherine Dulac of Harvard has shown that imprinting is far more common and more intricate than supposed.
Rather than supposing that all consumption choices can be ranked by how much they promote an agent's happiness, economists focused on the ranking itself.
Rather than suppose that there are multiple attention resources distinguished by reliance on a particular sensory domain (Wickens, 2002), it is possible to suppose that some other difference between the two tasks enabled their simultaneous completion.
Perhaps medieval Spain was less tolerant than commonly supposed.
Life as a hunter-gatherer was probably more intellectually demanding than widely supposed, he says.
The phenomenon of territoriality may be more widespread than is supposed.
