D1 is currently limited to 100 MB, and I'm doubtful it's meant to be a complete database. As I understand it, it's more for "manual cache" purposes and not for hosting everything there (think about 100 TB of data).
Regarding your second comment, while it's true that all the solutions you mentioned allow you to deploy a DB, they are offering between 5-10 locations around the world, compared to 100+ locations of Edge solutions.
Anyway, that's not the main point. I still don't think it's the right way to create read replicas for all your data in all locations. There should be a better way to copy only the relevant data (the data you want to fetch with low latency).
Regarding your second comment, while it's true that all the solutions you mentioned allow you to deploy a DB, they are offering between 5-10 locations around the world, compared to 100+ locations of Edge solutions.
Anyway, that's not the main point. I still don't think it's the right way to create read replicas for all your data in all locations. There should be a better way to copy only the relevant data (the data you want to fetch with low latency).