Meryl Streep long ago proved she can act. In Into the Woods, as she did in 2008’s Mamma Mia!, Streep proves that she can sing, too.
One thing, though: You probably wouldn’t want to sing in a choir with her. Performing in an ensemble requires more restraint than performing a solo, as your goal is to blend with the other voices, not to stand out. Whether she’s singing or acting, Streep often seems incapable of exercising this kind of restraint.
Maybe it’s not her fault. Maybe her directors think to themselves: “Hey, I’ve got Meryl Streep here. Why shouldn’t I take advantage of the situation by letting her deliver a Meryl Streep-style star turn?”
Well, there’s nothing wrong with that, as long as she’s the star. It’s not so good when she’s merely one member of a large ensemble, as she is in Into the Woods. The fact is that whenever her Witch is on-screen, the other actors basically disappear into the fairy-tale-style woodwork.