Text “flows” in most word processors! It depends whether you think of a “Dorico project” as “music interleaved with bits of text”, or “text interleaved with bits of music”.
A hymnal is a special case, because each item of text and music is fairly short and self-contained, so it doesn’t need much automation of the “flows”. But there are books where the format is essentially “continuous text that flows from page to page, plus hundreds of music examples.”