I think nobody can control or own the bitcoin system like they can not control and possess the technology by email and the internet. I think Bitcoin is no different than a mobile application or program that offers a personal Bitcoin wallet and allows users to send and receive Bitcoin.
Developers can indeed improve Bitcoin software, but they can not enforce changes in the Bitcoin protocol because all users are free to choose the software and version they want to use. In order to remain compatible with each other, all users need to use software that follows the same rules
The problem is that if some software developer wants to enforce his changes to Bitcoin, then he can easily create a forked chain. Ever since the first forked coin was created (Bitcoin Cash), we had dozens of such forked chains.