Share… on a list now has a row for everyone in the workspace: No access, Can view or Can edit. Its owner, the channel’s managers or a workspace admin choose it, and only for a list in a public channel — never its guests, and never a list in a private channel or a direct message. Sharing a list or a canvas with a channel posts a message there from whoever shared it, which shows the list or canvas only to those who can open it.
A list whose owner’s account is deleted now has no owner, rather than quietly going back to whoever made it. The channel’s managers and the workspace’s admins look after it, and any of them can take it with Take ownership.