"It is only recommended for children."
Translation:זה רק מומלץ לילדים.
I think the difference here is between impersonal 'it' and personal 'it'. For example,
It's recommended to sleep at night = מומלץ לישון בלילה - here dropping the pronoun is recommended.
(I watched a movie yesterday.) It's only recommended for children = הוא מומלץ רק לילדים - here you can't drop the pronoun.
Impersonal 'it' is often dropped in Hebrew, though lately it's becoming more common due to influence from English; personal 'it' isn't dropped.
I guess EitanAltsh meant this (I got it from Tips & notes)
Several words in Hebrew that express modality (that is, likelihood, ability, permission, obligation, etc.) do not require a subject. For example:
מומלץ לא לעשות את זה
It is recommended not to do that.
(And not זה מומלץ לא לעשות את זה)