Absolutely. I have boy/girl twin 5-year-olds with Autism. Because it was caught and early intervention started shortly after they turned 2, the girl is going to a regular kindergarten this fall and her brother will be in the special ed. classroom at the same school (instead of the special ed. school he would have been otherwise projected to attend).
And it isn't just that their results were atypical (although we note that the girl is going to become the program's poster child for success) -- the program as a whole is seeing an increasing number of students being placed in higher-functioning environments than a few years ago, which can be directly traced to the increase in emphasis on early intervention.
Yes, of course "special needs" is over-broad and many kids are over-diagnosed. But there are still many kids with true special needs, and early intervention has worked very well for them.
One of my aunt taught third grade. She was given the boys who had trouble learning to read. She recognized that many were physically not on target. With help of the local university she developed an atmosphere that met all needs. Her “boys” were always up to level and beyond by the end of the year. Received teacher of the year twice from the state....Unfortunately others didn't pick it up...Too expensive, although, she somehow managed to fund it with her single parent teacher's income.