@raphaelblg thanks for the reply.

I tried the suggested edits, but came up with the following error:

[DLT_VIEW_SCHEMA_WITH_TYPE_NOT_SUPPORTED] MATERIALIZED VIEW schemas with a specified type are supported only in a Delta Live Tables pipeline. SQLSTATE: 56038; line 1 pos 0

The docs for DLT to create materialized views doesn't indicate a way to add column comment as you noted.