That comment proves that you know NOTHING of how the game (or the player) works. Spacing is not mindgames, it's technical skill. You don't play around with an attack and make it unpunishable; you practice it until you know how far it reaches, how you can cross it up, where the knockback trajectory sends you, is it disjointed or not, how much damage it does, is it multi-hit, does it auto-cancel, etc.... It's dependent on a character. Mindgames is dependent on the player, so you can't practice these things like you would spacing. You develop these by keeping up with a match and 'out-smarting' your opponents.
You would say that a 'bear' is not the same as a 'wolf' , but they both fall under one huge category: animals. Would you argue that it's just to make everything look prettier, or for ease of access when we want to study them/talk about them? We COULD say "a bear is not the same as a wolf", but we CAN'T say "an animal is not the same as an animal", since it makes no sense. It's just a way of categorizing things to make it easier to talk about them, or to refer to them. People in SWF just find it easier to say "mindgames" than to bring up the proper term, or talk properly about the message they want to convey.