My point was that you already know their age; and have presumably considered that, and still disagree. It's not new information. (By the way, can you clarify the exact conversation you're referencing? I don't remember off-hand.)

I view this retort as an admission that the evidence I can access is against them. I've even been told explicitly that they don't expect me to agree with them.

There are two possibilities. Either they are wrong, or they are right, and I shouldn't agree.

To the extent the experience claim was true, I would take it into account without them mentioning it. The easiest counter is to look at whether everyone of their age and similar enough life story agrees with them.