> However, if you're already arriving or leaving on a long distance flight, the whole overhead of getting to/from/through the airport disappears and those 1.5 hours start making a difference.

There is a workaround for this. For long distance flight, take a company where the international/local connection takes place outside France: KLM through Amsterdam, Lufthansa through german airports, Brussels Airlines through Brussels...

This is already what I always do when I have to make a long distance flight because Paris Charles de Gaulle airport is horrendous and Air France is prone to mass cancellations when there is a strike.

But this is doable because I live in Toulouse which has bad train infrastructure but is well connected to the rest of Europe by plane.