Me: “...the most popular Protestant music form was for most of the 19th century. ...the so-called "bulgines...” &c.
You: “The later ones adopted after c1830, once chantying took off,...”
Yup, them are those.
As to the others, have you reread the OP lately?
Cyrus Tiffany's (c.1738-1816) maritime musical tradition was Western style martial. The man was born free & Black before the Colonies became American.
In your version, what Gulf Coast West African-American influence and impetus finally kicked the so-called 'proto-shanty' out of its 2200+ year-old proceleusmatic nest?