Is Gregory Kurtzer the owner of the RESF?

Yes, Greg owns the legal entity of the RESF (somebody has to!).

This is common within the open source community even for large projects. For example Ubuntu, Python, OpenBSD, Slackware, Ruby, Perl, and even the Linux kernel itself, all are (or have been) owned and/or controlled by a single individual. That does not and should not detract from the value, integrity, or impact of any of those projects.

By ratifying the bylaws and charter, Greg has turned over the control of the RESF to the structure defined within those documents. There is now no single leadership position and everything is run by elected boards and contributing individuals. This means that if Greg does a good job, he might be elected to a board seat, and if not, or if he is unavailable, others will be elected.