It appears that right now the alphabetical order of components determines which compoenent lead is assigned as the default owner. It would be nice to be able to determine a custom sorting. That way when folks choose multiple components the Jira will go to the component that is more specific (well, that's how we would use it... we have components that touch many other components, so technically they should be marked, but if there is a different component selected that owner should be the one starting the investigation).

Either way, an explicit ordering (with alphabetical as default) would be nice to have.

Documentation: https://support.atlassian.com/jira-work-management/docs/organize-work-with-components/#Select-a-default-assignee