BNP Paribas offers great work/life balance in most departments, depending on your position, team, immediate supervisor and market conditions you might still struggle with leaving work on time and/or fully shutting off on the weekends etc.
Such pressure is expected if you are working with quantitative models based on constantly changing market dynamics. Especially commodity markets whether energy, agriculture or precious metals get disrupted easily by political developments, weather events, holidays and so many other things. Equity and fixed income desks usually have similar realities as well. So, high-intensity (at least time to time) and at least moderate amount of pressure is implied and should be expected in quantitative analyst and similar positions.
Other than that, I felt BNP Paribas values good character so you get decent colleagues and usually good bosses (so hopefully there won't be too many American Psycho type bankers at your branch or HQ). Another advantage is they offer better remuneration packages than most - great pension contributions, dental coverage, health coverage and sometimes even spa and acupuncture coverage if you're into those and think they might improve your well being.
Overall though, I must say BNP Paribas is usually known for its great support for employees, understanding and supportive culture and very inclusive as well. So I appreciate this company for taking those values seriously.
Finally one remark I'd like to make is I can see someone who aspires to become a world-class quantitative analyst/trader/IB banker/PE analyst etc. being a bit disappointed due to relatively more chill work culture.
If you are looking for cut-throat competition and bleeding edge you might want to find something more special in your niche. Having said that I believe bulge brackets like BNP Paribas offer great career options and also do a great job preparing young financiers for more interesting opportunities (if pursued) in the future.