We want customers logging into the service portal to see only open tickets by default. Closed tickets may still be accessible, but not as the initial or default view.
Ideally, the customer should be able to switch to a full overview, but the experience should always begin with the most relevant list: the tickets that are still open.
Hey @ikihub,
Thank you for posting here! 
I wanted to let you know that this seems to overlap with this existing idea here:
To help increase visibility and streamline feedback for our Product Team, we encourage consolidating similar feature requests. I recommend that you add your upvote and any additional comments to the existing thread linked above.
Hope this helps point you in the right direction!!
Sam, Community Manager