Topic: Why wasn't Psychonauts ever put on GameCube?

I just bought the game for my computer. It seems right up GameCube's alley. Did the developers have something against Nintendo?

Psychonauts was released back in 2005, which is around the time most third-parties started completely ignoring the GameCube when it came to multi-platform releases. And, aside from a handful of titles, the last two years of the GCN's life were a barren wasteland when it came to good software.

It's an old cliche at this point, but good 3rd-party titles have often had a really hard time finding an audience on Nintendo's home consoles since the move to 3D. I assume Majesco/Double Fine simply didn't think a GCN port would be worth the time and effort.

So the game was "too good" for GameCube?

I think their concern was more that a GameCube release would sell very poorly, and had little to do with any kind of anti-Nintendo sentiment.

It was originally an "Only on Xbox" title. But when Microsoft decided to not publish it, I assume Double Fine did whatever they could to recoup the money spent. It was, at first, still supposed to only be released on the Xbox and PC. But Majesco hired an outside studio (Budcat Games maybe?) to handle the PS2 port.

The parties involved wanted to try to make any money back on it. Having a nearly completed Xbox version running, it made little sense not to release on that platform. And since the PS2 was a market juggernaut at that time, the publisher wanted a piece of that action. The game was in development since 2001 and had it's Microsoft specific funding pulled in 2004 (Largely due to Fries' departure from MGS).

3rd party Gamecube games generally sold poorly, especially when compared to the PS2 and XBOX releases of the same games (with a few exceptions, like Soul Calibur 2, which makes sense). That, and the amount of people actually buying games for their Gamecubes in 2005was destitute, with the exception of Resident Evil 4. It just wasn't a viable platform for publishers to put games out on from a money perspective.

Sadly the last few Nintendo generations have had something turning away third-parties.
On N64, it was the choice to use cartridges over CDs (less memory and higher cost).
On GameCube, the discs were smaller (about a third the memory of standard DVDs on the other two).
On Wii, lack of HD.
We'll have to wait to see what happens with WiiU.

Afraid of poor sales? Quite ironic because the game sold terribly as it was - despite how good it may be.

3rd parties don't try to make many games successful on Nintendo so Nintendo games carry the system so 3rd parties don't try to make many games successful on Nintendo so Nintendo games carry the system so 3rd parties don't try to make many games successful on Nintendo so Nintendo games carry the system so 3rd parties don't try to make many games successful on Nintendo so Nintendo games carry the system so...

Unfortunately I think the only way this would change would involve something like...I dunno "Nintendo announces Wii U to be the only traditional home console to have Half Life 3, Guild Wars 2 and X-com" or something else, with the ports entirely funded by Nintendo for this to completely change.

It seems to me like the general mentality is that Nintendo fans simply don't like good third-party titles. I'm pretty sure that's not actually the case but it sure seems like it is sometimes.
I've been a Nintendo fan for years, but I've already gotten sick of princesses being rescued over and over again by elves stocky guys with annoying voices.

I'd consider the first half of Psychonauts a great game.

The latter half, not so much. Far too long in the tooth.