Well, I wouldn't dismiss project right out of hand. Because in my test, I managed to make 100% manufac project much more profitable than 100% research (though I abuse the hell of Altarian Dark Research Lab. I didn't know it's a bug before this).
100% Science Slider (~700 beakers)

100% Manufac with Research Project (3k beakers)

Galaxy run on the fuel of research project alone (I have about ~5 more mature planets running on 100% manufac research project. Each contributing 1k+). Look, ma, zero science
.

Here are the manufac modifier.

And here are the science modifier.

Well, it was fun while it lasted
.
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On a more realistic note, I loaded up another non game-breaking save using a non-matured planet and checked if project is better than raw research/wealth or not. It is in mid-late game.
100% Science (~70 Beakers)

100% Manufac with Research Project (~140 beakers)

100% Wealth (~70 wealth)

100% Manufac With Wealth Project (~130 wealth))

And this is the base planet.

So, the answer is yes with caveat. From the base planet above, you can see that:
- It is not mature. I can still upgrade a few of the improvements.
- It was not properly specialized. The wealth or science improvements can be removed and replaced with 1 farm and 2 science/wealth building.
- In this game, I only got three ideo trait. So, a lot of passive bonus is not in.
- There are still some tech that can improve the buildings further, and tech that can add passive bonus (+manufac, + research bonus).
- I still have two more terraform tech not researched.
- It can still be enhanced further using starbase.
- I did not use manufac/tech capital in the planet above.
- The size of the planet is just 15 (mid tier).
So, all in all, I think that project can be better than raw 100% science/wealth, but only in on mid-late game (need time to research the tech, build all the improvements, starbase module, etc.).
A single planet may not be as crazy as to carry the whole galaxy like the Altarian above (Dark Research Lab abuse), but it can definitely be more profitable than raw 100% science/wealth in mid-late game. Project is not recommended at early game at all.