But that raises the question if you can play like that for top four, why not for the title push?

It's totally bizarre. You can't simply dismiss it as being unable to handle pressure because if they are under pressure to reach top four wouldn't they equally fold under pressure.

I don't believe for a second Wenger is telling them not to try to win the league or not put the effort in unless top four is on the line, so I don't get it.