Andreas Holck Høeg-Petersen’s review published on Letterboxd:
Damnit... This was not nearly as good as it should've been.
The horror is fine, and it is clear that Jordan Peele embraced that particular genre from the beginning when making this movie, and not as something he tacked on as the project progressed, which was the case for "Get Out". This time, however, it feels like the humour is tacked on, and when things get crazy and brutal, it is a damned shame that the movie can't stick to being terrifying but has to throw in a joke every once in a while (not all movies have to be Marvel movies!).
But that is not the real problem of "Us", which does manage to be entertaining and thrilling for most of its running time. The problem is that when it comes down to it, the movie is basically just a mess. There are a lot of elements that carries symbolic and metaphorical meaning, but they either have no pay off at all or are just played very vague and very safe.
I hate to say it, but take away the respect you (and I!!) have for Jordan Peele and you gotta admit, that this movie is no smarter than any of "The Purge"-movies. The main difference is, that the allegory of "The Purge" is in the synopsis and is a pretty interesting thought experiment, whereas the allegory of "Us" is played as a not-so-clever twist and is non-sensical even as a thought experiment. Sorry...
So, I guess you could be very kind and say, that it is 'open for interpretations'. But I think it's more fair to say, that it is no way near as clever as it and we wanted it to be. What a shame!