There may not be a deceit. but If there is one. it lies in discouraging a discussion of detrimental factors other than a possible constricted world-view. It also completely ignores the fact that age-related experience may be very useful in dealing with issues.
While our aging leadership does seem somewhat out of touch. younger leaders throughout the world are also experiencing difficulties.
This claim may ignore or minimize many other factors.
Younger politicians may make this claim to gain an electoral advantage. even if it is not 100% true.
I think the motivation behind this is the writers wanted to tell a story that sounded good even though it was not particularly accurate.
Some younger politicians are also guilty of entrenched habits and have jobs that have become entitlements.
If this claim makes older politicians more aware of age-related issues that could possibly be influencing them. then the claim is acceptable. even though it may not be 100% true.
Other problems also exist. and claims like this can be counterproductive and create an environment that can discourage younger citizens's participation. The statement also ignores or minimizes the fact that experience gained with age may be very helpful.