At 21, boys your age weren't your 'mate' cos you were already rolling with men twice their age.
Everyone understood, the boys weren't offended, they just worked harder to get better.
Now, you're 31, you're asking why men your age don't date women like you, why are they going for the 21 year old version of you?
Must be a trick question cos you can't be serious with that line of reasoning.