As announced before, Microsoft Stream (classic) is replaced by Stream (on SharePoint) in a certain term so please move your videos accordingly.

In this case, the following problems may occur.

• Videos on Stream (classic) owned by users who have quit (retired, graduated, etc.) our University will be deleted according to the replacement.
• Only the owners of the videos on Stream (classic) can operate, including downloading.
  Therefore, other users cannot access these videos if the owners have quit.

Due to copyright issues, ACCC cannot change the ownership of such videos without the owners’ consent.

Owners who plan to leave please transfer the ownership to other members beforehand.

See also:
Migration to Stream (on SharePoint) following the Discontinuation of Stream (Classic)
https://www.cc.tsukuba.ac.jp/wp_e/stream-classic-discontinuation/