Technically Bitcoin development stops if all the dev's stop or leave....
Thank you, now we are very close to the exact topic: A
small group of core devs actually release the code, who takes over if they are gone?
its open source. the codes already released.
There's no one in "control" of bitcoin. The code is open source. Anyone can contribute. The nature of the system is consensus, so You could add to it. Here's the downside. The node operators have to agree to your alterations or they simply do not run your version and you get a hard fork or whats known as a altcoin(you ALSO can be a node operator no one is stopping you). If you look out there you will see that there is 10,000 alt coins.
Not all of those coins are forks of bitcoin some are original code(they ARE a copy of the idea). Most of them fail. Right at about 99.995% failure