The risk here is that if one table has two fks to another table, the syntax becomes ambiguous. And the number of fks two tables have to each other may change over time. This means that an append-only change to a table may break existing queries that have no knowledge of the new column.

SQL addresses this via the natural join keyword `using`, where you enumerate the common columns between the two tables being joined. It isn't too convenient for your example unless your pk naming pattern happens to be `<entity>_id` instead of just `id` (note: this naming pattern has all sorts of other adverse consequences though). But it does provide convenience in some cases without introducing backwards compatibility risks as the schema evolves.