As this notes, there's several changes you have to make to your assumptions around the ORM interface. SQLAlchemy, for better or worse, supports "lazy loading" of relationships on attribute access - that is, simply accessing `user.friends` would trigger a query to select a user's friends. This kind of magic is at odds with async/await execution models, where you would instead need to run something like `await user.get_friends()` for non-blocking i/o.
It looks like they've done some good work in making the ORM layer work reasonably well with these limitations (https://docs.sqlalchemy.org/en/14/orm/extensions/asyncio.htm...), but I wonder if removing "helpful magic" like this will push more people to stick with the query-builder, rather than the ORM.