Which country ? In Asia-pacific region this is a dream! (to work exactly 8 hours) Likely Europe ?
I've never been in a company in France where working 40 hours (actually 35, 37.5 or 39 hours depending on contract and company size) was considered underperforming, for example. I've had two bosses who used to actually force some people to leave the office after 6pm or so (office time was 9-12/13-18) though I've never been one to stay longer than necessary myself.
In Canada however, I was expected to stay late in the evenings but that's just one company so I can't say it is representative of the whole country.
Absolutely not in my experience. And ironically even less so in France. Have worked in Dublin, France, Switserland, and Belgium. The workweeks as a contractor were respectively (38,38,42,40)