"Closed source" is reaching. As much as I think Doom shows why it should be desirable, let alone not taboo, it's always been the industry standard and applies to 99.99% of games.

The mediocrity as I understand was from the rift that developed in the team about the vision of the game being a sandbox vs a campaign.

However, I witnessed a new divide among the team which was less well-known; as more core game developers (such as myself) were recruited to help finish the game, a cultural gap emerged between the newer ‘gameplay’ team and the older ‘Sim’ team. The former group (which went on to spearhead Darkspore) was primarily concerned with how Spore played as a game. Were the mechanics engaging? Did the player’s choices matter? Was the game replayable? In contrast, the ‘Sim’ team carried the traditional Maxis DNA and was more comfortable with Spore as a toy box. Could the players express themselves? Was sharing one’s creations with other players meaningful? Did the game spark the imagination?

These cultural divides ruined Spore’s chances to be a focused, cohesive experience.

http://www.designer-notes.com/2013/09/

SimCity is the last time I was excited for a modern remake of a game, and likely the last. It was such an incredible letdown, you couldn't even open the game at launch because of the always online stuff. Most every remake of a classic has been terrible ever since, I'm happy to be proven wrong though.

that was the fate of cnc, they released the cnc4 for a cashgrab then pratically ruined the franchise(online version of the "spinoffs' dont count)