I've come to the conclusion that everyone is somewhere on the spectrum.
The question of whether to get a diagnosis is more about handling any issues that come from it. Some people need medication, some people needs extra help with certain things and some people just needs to know about it - in order to function in the way that makes sense to them.
If you need those things to function, it will help to get a diagnosis, because it can make it a lot easier to get that help, especially if it's medical.
But, make no mistake. Everyone has something. It's only a question of whether you need to treat it.
In a perfect world where there was no prejudice, we could be screening all school children and hand out paperwork along the grades, so you'd get an 8 in Math class and a 4 in ADHD. You know, just to get a full picture of the person.
But joking aside, there's no reason why teaching can't be more inclusive of these issues and just teach everyone as if they have autism and ADHD, even if they do not have a diagnosis. More often than not it's only a matter of being allowed extra time for certain tasks or a slightly more pedagogical approach. Everyone can benefit from that, so it's completely wrong to place diagnosed kids in special classes, when what is really needed is better educated teachers.

Turns out, you don't actually need a good guy with a gun.
You need a guy who is good with guns.