In sufficiently small companies yes it makes sense for everyone. In larger and more regimented companies doing the Greenfield project can (and often does) lead to promotions and higher earnings.
Teamwork is fine, but when salaries and promotions are individually negotiated you have to look after number one.
The level of politics, promotion, promotion packets, leveling is a whole different level. That is not to start on PIP, hire to fire, etc...
You need to know the game if you're going to play it.
I have the highest rank and salary on my team. I am more than happy to send high visibility work to my aspiring team mates. What goes around comes around, if not in the form of immediate salary then in the form of connections and references down the road (which is a much bigger driver of salary and rank anyway).
Playing a zero-sum game at work at the expense of your colleagues is penny wise, pound foolish, even if you truly do only care about yourself.
I'm not against spreading credit. I'm against misrepresenting situations to spread false credit, which creates incorrect perceptions and leads to poor decision making and political tension. If an individual did a unit of work, I will acknowledge that, to the extent that it is true. If an individual jumped on a grenade and did unpopular work, I will praise that individual for doing that work.
This is not antagonism towards teamwork, it's to make the team function better by ensuring information propagation is accurate, that the people pulling the weight in the team feel recognized, and that free riders are held to account which is a form of respect to the productive team members.