What engineering challenge for verification on Venus is considered greater than landing on Mars's dry plains?

Developing materials that can resist concentrated sulfuric acid for months

Verifying any potential biology or chemistry within the Venusian clouds presents an immense materials science hurdle that surpasses the mechanical difficulty of landing a probe on Mars. To conduct long-duration, in situ analysis, a spacecraft must function precisely within the cloud layer while simultaneously resisting corrosion from concentrated sulfuric acid. Developing specialized materials capable of withstanding this highly corrosive chemical environment for months, while also maintaining operation at the specific pressure and temperature point where water vapor is available, represents a technological challenge considered more daunting than simply navigating and landing on Mars's cold, dry surface.