Songs about home have emotional power. Underlying them, often, is an expression of something irretrievably lost, usually through age and time. Songs about early love are in the same mode. Stephen Foster songs are an illustration. In the period in which he lived, life could be short and harsh. Graphic lyrics did not seem so alien or distasteful. Many other parlour ballads of the period, and later, can have a similar force. Even the Everly Brothers sang a few (e.g. Midnight Express). Sentiment or slush? I don't think it is entirely in the eye of the beholder. Songs of this sort, when sung with conviction and absence of sarcasm (a modern disease) are still effective. Of course, there were also a lot of pot-boiling tunes in this mode which are not worth the bother.