I would be nice to filter by who is watcher on a group of Ideas, so we can understand who are the interested stakeholders of a group of ideas.
Thank you for the idea!
You can encourage your stakeholders to vote on existing ideas. You can then use existing filters and reporting to better understand who the interested stakeholders are for a group of ideas.
Watchers behave a little differently and may not be the best way to report on interested parties. For example, watchers can be inherited and may not best represent the key stakeholders.
For this reason, we are unlikely to implement this idea. However, we will continue to monitor for community feedback and overall priority alignment.