In our Jira software security setup, if a field is modified or deleted in one project, it affects other projects.
Can security be modified so that super-imposed on the usual security setup, a member of a Team cannot modify fields or other entities that would affect projects associated with other Teams?
And, is a better approach to allow changes only in a Sandbox, and require a procedure by which those changes are moved to Production?
Currently that is not possible, once you have Jira admin permissions you have permissions to make changes to everything within Jira. Atlassian is working on a more granular admin role, and it currently on the roadmap to be introduced sometime in 2023.