Milchin was a well-liked director, but I admittedly don't like many of his films all that much. In this one, nothing bad happens to anyone, which gives it a sort of overly-sugary feeling. It's nice that the boy returned the umbrella to its owner at the end, but he should have done that to begin with, even if that downpour of rain at the end seems to have been, like many things in the film, entirely imaginary (since the old lady isn't wet at all when the umbrella is returned to her). It feels like there's supposed to be some vague lesson here; the boy feels guilty and heads off to return the umbrella at one point... but apparently he could have just safely kept on playing. There's no real human interaction between the boy and anyone - he's daydreaming and playing by himself for basically the entire film.

On the other hand, animation film critic Sergey Aseninin his 1971 book "Magicians of the Screen" (Волшебники экрана) has only nice things to say about this one (on pp. 208-209), calling it an example of Romanticism in children's animation, and praising the "clarity and precision of its visual language". He's especially fond of the part at the end where the boy boldly walks through the rain under the magical umbrella that hovers above him, with more and more wet toys joining his march. I like admittedly like that scene as well. Although while watching it, I was also thinking "stop getting distracted already, return the umbrella to the old lady who is probably getting wet!"