I very much would like to see this feature added in the list view & when an error is reported to Slack (or another destination). We're a larger team with about 8 groups, at times it's hard to know which group is owning which error & sometimes one thinks another owns it.
If we knew an error was already owned when posted in slack, we'd be better able to respond to new events. Currently, we perform a bit of a scramble for every posted error (Who owns this? What's its impact? is it critical? What's it status? etc). Clearly owned errors will help direct discussions to the appropriate owner & allow the team to only respond critically to unowned errors.