I think the problem is that it’s difficult to think of this on a country-by-country basis. I’m in the UK. One of my friends works for a hedge fund in London and has an appalling work-life balance, long hours, little opportunity to work-from-home. Another works for a charity based in London while working-from-home in a regional city for all but one day of the month, and works reasonable hours and gets every other Friday off. My own experience is somewhere in the middle. The difference between our individual experiences in the UK will dwarf the differences between the UK and another European country.
I can completely believe that your own relative experiences of Austria and the UK could be very different to what’s shown in the diagram because work-life balance is so much more dependent on what line of work you’re in, who your employer is, what stage you’re at in your career, etc. Except in extreme cases, these things will count for more than national differences.
Another reason it can be tough is that certain metrics are defined differently between counties.
Many metrics will list the UK a having one of the highest holiday allowances in Europe since legally full-time workers are entitles to 28 days off, however the UK includes Bank Holidays (8-9 days) in this total. For comparison, a country like Austria has a minimum of 5 weeks holiday (25 days) but this is IN ADDITION TO state holidays (of which there are 13, but some will be on weekends so the absolute amount varies year to year). Centrally this end up with everyone in Austria having something like 33-34 days off.
I’ve yet to see a list that accounts for this, so most have the UK right near the top. I would bet that this metric is no different.