everyone's missing the point. they literally said that they're songs are about common topics, as are most k-pop songs. there's this false narrative that blackpink lyrics are uncommonly "shallow" when they're not. some songs are meant to be emotional, some inspirational, but other times it's just to have fun. not every group of singers and songwriters can nail all the common subjects like they do.
also I know most of youse don't like English class but some of us do and analyze things that aren't necessarily all that deep because it's fun.