Definitely not true in the UK, definitely not true in The Netherlands. Not true among my Paris based friends, had dinner with some of the latter which included

Definitely not true in the UK, definitely not true in The Netherlands. Not true among my Paris based friends, had dinner with some of the latter which included someone who was on their third startup and a few Sciences Po / X types who have the kinds of jobs you would expect and the latter were extremely interested in the what the former was up to and how the startup ecosystem worked. Definitely not a sense that they thought having tried and failed to start a tech company was somehow a bad mark - and realistically grande école types tend to be very status conscious so would have picked it up if it was there. I can't speak to what older people, people outside of Paris would think of it. I would guess much more conservative.