That would be ideal, the dev and the community all contributing to the advancement of a coin.

But at the start, someone has to lead, someone has to inspire and convince people that a project is worth supporting, either for the betterment of society or financial gain. I think that challenge falls on the shoulders of the dev or founders because he or they have the initial vision and expertise to develop the project.

With so many competing altcoins and scams perpetrated by many devs and their supporters, building and growing a community around an altcoin is not that easy.

That's why it's quite admirable to see some devs pursue projects amidst so many odds and challenges.