A deliberate foul results in a free kick or penalty for the other side, and perhaps a card, and therefore justice is more or less done. The same goes for a handball as long as an official sees it.
But a successful dive results in a free kick or penalty for the cheating side, and perhaps a card for an innocent player, and often results in an unjust scoreline, so justice is in no way done. This is why I think a conscious attempt to deceive the officials and basically manufacture an unjust scoreline should be treated as a worse offence, as it is hardly any different from match fixing.
Fouling is a largely unavoidable part of the game, and is righted during the match more often than not. If the wrong decision is made by the referee, then the blame should mostly be on the officials for getting it wrong.
Conversely, if a player successfully and purposefully deceives the officials, then it is the player who should receive more of the blame. The only problem is proving for certain that it was an intentional dive.