We will be adding the ability for administrators to expire external users’ access to entire site collections after a mandatory expiration period, as we discussed at Ignite 2018. That feature will be rolling out in CY19Q3.sanjeev commented
There might be time when you want to expired links that you shared rather than deleting the item itself after some period of time.
Thanks for the suggestion. We’re looking at it.sanjeev commented
Would be nice if you can password protect any folders or files that you want to share.