According to some quick Googling, this seems unlikely (see below). Europeans do get more paid time off than Americans, but I doubt they're working 30-40% less than Americans.

> The average number of weekly hours worked by full-time workers in the European Union was 37.1 hours a week as of the third quarter of 2021

Source: https://www.statista.com/statistics/1197097/average-working-...

> For those [Americans] in the typical age range for full-time work, the national average landed at 40.5, indicating that most employed adults work a 40-hour workweek

https://www.zippia.com/advice/average-work-hours-per-week/