It’s a good thing. Is it a good or bad thing that this child would be forced not to smoke?

It does not matter if a vice is chosen or unchosen. Smoking is a great example. You may not choose a tobacco addiction.

Situation A: you have the freedom to choose to quit or not. Quitting results in more freedom. Not quitting results in less. The total freedoms available to you at any time are the freedom TO quit and the freedom OF quitting

Situation B: You have no freedom to choose to quit. Your total freedoms are: freedom from quitting.

So your freedoms have decreased in situation B. We have to ask if personal freedoms are preferable to better outcomes.

The difference is that freedom is independent of opinion. You are either free to do so lawfully or not. But if I say “it would be better for you to not have that freedom”, I need to demonstrate what “better” means. And there everyone often disagrees.

Forcing someone to stop smoking is not giving them freedom

I think saying this largely denies the cultural implications of many religiously associated garments and symbols.

Most religious symbols are not just that, they’re cultural ones. People adopt them, change them, redefine them. Drawing lines between religion and culture is very difficult so attempting to stop someone dressing some way is just a restriction of freedom, regardless of religion.