Just for context, 400 aircraft is only marginally smaller than the current operational combined wide bodied fleet of KLM, Air France, Lufthansa, Iberia and BA.
It's all very well being ambitious but there comes a point where wild claims starts to hit your credibility. What business plan is he operating under where he sees that as an ultimate goal? Does he see it operating from several European countries?
His entire plan seems at odds with the way other people do it. Yeah, they might not be as glamorous as aviation was once perceived but most of the national airlines, importantly, make a lot of money.