It seems to me Rails has been doing this but better for years.
It definitely keeps atomic and historical migrations, but also maintains a schema.sql file that can be loaded as a one-off (e.g. for mock DBs in tests).
I'm curious what makes it better than the approach in the blog?
If it's this:
> also maintains a schema.sql file that can be loaded as a one-off
That's exactly what the declarative files provide