When I was in elementary school, every kid who didn't form sounds like "normal" went to speech therapy until they did. By 6th grade none of my friends lisped or stuttered or spoke with excessive sibilance. S-backing was not a thing then (it seems half cultural/regional now and half unconscious/untrained/lazy but I have nothing but my experiences to base that on; it is not a conscious choice for anyone I've asked) but today, I hear all of those things so I have to assume that there is not very much speech therapy any more.