Erik Darling continues a line of thought:
Temporal Tables are different, because it will add new, and drop removed columns from the history table as they change in the base table. It’ll also push data type changes across. But the history table will not have the various permutations tracked. It just mirrors current state.
The one thing I do want to mention is that the column Erik calls JunkDate
isn’t junk at all in its proper context—it’s the row end date for a Kimball-style dimension. I get that it isn’t useful in the “type 1” table, but it’s quite useful in the “type 2” table and the sorts of queries temporal tables were expected to solve use the row start date and the row end date together to give you an idea of whether the version of the row you’re seeing is the current version or not.