It is the same in my context. It is difficult to promote the use of open resources from that point of view. There is a fear of losing control of the resource and becoming dispensable as an expert teacher in a certain content, or losing the reference to its authorship (although all content has multiple layers of authorship).
It is as if another teacher, having the script of the play, could teach with the same background as the experienced teacher. However, when the play is in progress it brings into play other teaching skills, the ability to make the students' learning active, to make the experience more inclusive, to arrange the learning experience in the most student-friendly way, to respond as best as possible to what happens, to ask good questions... there is much more to designing the classroom experience than having the ideal resource for that content.
It may feel very lonely for individual teachers in their classrooms and there is a need for a more objective or closer professional recognition among colleagues in sharing practice, experiences, challenges, with the aim of creating a collaborative culture of sharing educational resources, and helping us to build better resources together.