You just don't know what you're talking about. Sargeras was framed as the endboss for a very, very long time (until they brought up the Void Lords). The Jailer is said to be behind Sargeras. And in your world this doesn't make him someone - at least when it comes to the horrendous lore in Shadowlands - above Sargeras aka endboss levels?
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Have you read the comment? Do you know what events the Jailer is said to be responsible for? Sargeras? Lich King? Stabbing of Azeroth? And a lot more. And that doesn't make him exactly that?