I don’t think that it is a major difference between European and US certification rules as such, just a difference in control design. After all there are no changing stick forces in an airbus, the only force is a spring setup in the stick itself to return it to neutral, completely independent of control law and speed. Trim is always automatic except in direct law, and most people forget at first to trim manually if they happen to find themselves in direct law, which is the last fallback level available.
That said, the airbus FBW design is older than the Boeing one, and I think that Boeing learned from what happened with the Bus.
By the way, it is absolutely astonishing how fast one de-learns trimming on switching from Boeing to Airbus. Just my personal observation. Simply because it is never needed in normal line operation.