It should be noted that in kids nobody can say whether it will _always_ interfere with their daily life in a material way. Autism diagnosis in a preschooler usually (90%-ish?) means it will, which is amazingly accurate if you think about it. But it's definitely not 100%. So in little kids, the diagnostician is saying they _think_ it will interfere with daily life (and that it is interfering today, but saying that about a 3-year-old doesn't necessarily mean always and forever).

See also http://intellectualizing.net/2013/09/21/the-trouble-with-ove...

Another issue is that it's sometimes easier to have a personal difference interfere with school than it is to have it interfere with real life. That argument is at http://intellectualizing.net/2015/03/12/schools-are-disorder... Real life is more flexible than most schools.