Mary Poppins Returns comes 54 years after the release of the original movie, and watching it can make you feel nostalgic for the first film.
This second installment has great performances by everyone involved (still, I don't know why Hollywood lets Meryl Streep sing, it's not her strong suit); however, despite good acting, there is nothing memorable about the music. The genius that Sherman and Sherman lent to the Julie Andrews version is not here, and it's quite a loss for the film.
In addition, it has only a few scenes that contribute to the plot. The rest have nothing to do with anything and are strung together as song & dance filler to reach the 130 minute runtime.
There are some things to praise the movie for. Dick Van Dyke for one. It's amazing to realize he was 39 when he made the original, and 54 years later he is there to hoof it up and make jokes that circle back on the first film. The animation matches the 1964 film's style which is pleasing.
For all it's pros and cons though, kids seem to be enjoying the film, and that's all that really matters.