Stefanos is speaking his mind here. He's always been that way. When he's devastated, he usually pours it all out in the press. Doesnt hold back or give excuses. He knows Felix has his number from the junior days. He knows it's a difficult matchup. Instead of giving excuses, he's being honest that it's going to be a difficult challenge.
The self righteousness and judgemental posts on these boards is just something else. Only if a player plays, acts and behaves in a monochromatic way, along expected lines, he's liked and praised for his "maturity". You stray from the beaten track even a bit, and you are branded a "weirdo", "pretentious" "fake" as though you all know him personally. If Fed was an up and coming youngster now, he'd have been hated here for his temperament and "arrogance". Thank God he emerged at a time when there was not much social media and internet ruling our lives. So he was given the space to make mistakes, mess up, make adjustments and learn to be a better player and a better person.