I would check the linked article that shows up on the tile and within the media editor regarding Mixed Content as that is most commonly the issue:
Pay particular attention to two parts:
Enable ‘Allow Insecure’ on Chrome
Or in newer versions of Fully Kiosk: Advanced Web Settings → Mixed Content Mode → Always Allow Mixed Content
Check the note about Chromium 111 and the bug Google introduced. Using nip.io as mentioned in this reply seems like a decent workaround for most people.
Efficient Streaming Alternative for Blue Iris
If you’ve got Blue Iris 5 (or otherwise have UI3 installed), check out this post about using the embeddable live views which are much, much more efficient at streaming from Blue Iris: