do you think the older we become the less desirable we will be?

From personal experience getting past 40 my desirability as an employee and for relationships has seemed to reduce every year. I think those that get both when they are younger and manage to hold on to both for the rest of their lives are very fortunate indeed. Those that lose one or both and have to try and find them later in life are really going to find it harder as there's both less opportunities and less interest.