Joshua Dysart’s review published on Letterboxd:
The opening bit, with the Tramp trying to do anything he can to get rid of a disregarded baby that's found its way into his arms, is played for laughs but is powered by profound pathos. The lives of the poor are worthless and, as people, they are unwanted.
The bit escalates to the point where the Tramp considers dropping the screaming infant into the sewer, but his better angels (later, literally angels, in a sort of filler dream sequence) finally stay his actions and the Tramp's heart is melted, his fatherly destiny sealed in a single beat of easy emotionalism that Chaplin would come to traffic in, though here, in 1921, was a revolutionary combination of comedy and drama.
You can't blame Chaplin for the emotionalisms. His own firstborn son, Norman Spencer Chaplin, entered the world malformed and turned out to be incompatible with life, dying just ten days before production on this began. And, of course, Chaplin himself grew up in desperate poverty and was shuttled through the workhouse system as a child in his native England.
It's all up there on the screen. Marred only by the closing sentiment, proven false by the march of history, that the suddenly wealthy will save those of us who are less fortunate.