Your donors have important things they want to accomplish before they depart this world. And you get to help them do that.
Even when a donor is no longer able to give, you should honor their lifetime’s commitment to your organization.
The only reason you should care what age a donor is, is so you cultivate and steward that donor appropriately.
When constructing a caseload for your major gift efforts, don’t make any decisions about who you will add based on age biases. Stick with what is known and true from the facts: older people give more.