I agree it depends. the boy I work with stims vocally(though he doesn't speak at all ever), with hand flapping at his ears, rocking(while sitting on a chair), clicking the computer mouse, chewing headphone cords and when he's in his body sock he started spinning last week.
His is 8, going into Grade 4, but we look at the future. Are his stims something that is socially acceptable now(most aren't) and will they be socially acceptable when he's an adult.
his sensory needs are extreme & very quick changing.
His vocal stimming is ear piercing & the one we try to work on the most, they're quite often loud monkey screetches.
The hand flapping at the ears we leave alone until it gets excessive. Then we try & redirect it to a more socially acceptable hand flapping onto the thighs.
Rocking, sometimes is something that most kids do other times is definite stims. when it gets excessive we try & stop it. Then he goes into hand flapping at the ears & we will redirect that to hand flapping onto his thighs.
Clicking the mouse, we try & stop. 99% of the time it's becuase he has zero patience for waiting for the computer to do what it needs to do. We'll leave the computer when he does it too much.
Chewing the headphone cords, we're working on getting him to chew gum instead but he swallows it. We've tried chewelry & stuff but he drools so bad with it he'll fry the keyboard instead. They're supposed to order cordless headphones but so far haven't.
Spinning, so far it's ONLY while in his body sock, but because it's new & I can't have him deciding to do it while going down the hallway I stop it.
It isn't so much that stims should be redirected, but to find ways to deal with the sensory needs so he doesn't get to the point of stimming(keeping his sensory needs balanced). Then if they do stim to find stims that will be socially acceptable(no point in teaching something that'll need to be untaught later)