What is a Late Diagnosis? It’s in the Eye of the Experiencer

I get so frustrated when I read of a late assessment for autism at age 20. Of course I am relieved whenever anyone finds out, but there is so much of life you regret you are unable to change at 40 and beyond.
The topic of What is #LateDiagnosis has come up on Twitter so I’ve drafted my own framework. I admit to my privilege of being a white, middle class person in a country where autism is better recognized. If I were a woman of colour in a rural area or third-world country, assessment would be unobtainable.
WHAT IS #LateDiagnosis ?
Age 7 Late diagnosis for a boy; typical to early for a girl
Age 12-17 Late for a girl; very late for a boy
Age 18-20 Sadly late for school help, but person largely avoids ABA
Age 25 Frustratingly late—too late to qualify for employment/transition services
Age 30 Intolerably late adult diagnosis; usually after breakdown and/or several misdiagnoses
Age 40 Bewilderingly late; usually after child diagnosed. Childless go undetected
Age 50 Painfully late—at expense of relationships and mental health
Age 60 Tragically late—sometimes due to a grandchild. Could have explained your life
Age 70 Appallingly late—mask is now firmly in place
Age 80+ Unfathomably late: diagnosis may not matter—mask goes back on in care homes
A recent and rare research paper on the topic. https://www.tandfonline.com/doi/full/10.1080/21642850.2019.1684920
Part One of Two.