Despite the marketing the ORM is very much distinct. You can use SQLAlchemy without ever touching or even knowing about the ORM.
The Expression Language on which the ORM is built on is more powerful than the ORM itself. You can do asynchronous IO with the Expression Language or generate SQL with it that you couldn't with the ORM.
This distinction matters. You can't just point to somewhere in the SQLAlchemy docs and say argue that because SQLAlchemy allows you do to X, there exists an ORM that can do X. Calling SQLAlchemy an ORM is a simplification that may be fine in some contexts but it ultimately isn't true.
"The Python SQL Toolkit and Object Relational Mapper
SQLAlchemy is the Python SQL toolkit and Object Relational Mapper that gives application developers the full power and flexibility of SQL."
So I would say it is in fact an ORM even if it is also a toolkit.