Indeed. One could look at the GDP per hour worked.
France and Germany GDP per hour worked is only about 6% less than the US (while it was mostly the same until 2008) [1] [2].
Seems like most of the difference can be explained by stronger work-life balance policies chosen by European (sick days, holidays, earlier retirement and parental leave).
[1] https://i.imgur.com/zuZ4pYz.png [2] https://data.oecd.org/lprdty/gdp-per-hour-worked.htm