I think the main problem with this show (and by extension books too I guess) is that it tries to be historically accurate while having a fictional lead who happens to be the most famous and respected person in the region. That means Uthred never really gets anything of note, and they have to find out very contrived way of taking everything away from him. Like you can't make him a proper Lord of a noteworthy place because he'd have to replace someone from the history books for that which the writer doesn't wanna do to maintain his historically accurate fiction. After several seasons of Uthred being a one man army for Saxonsbut still getting bent over, it's starting to get a bit noticeable.
If it went the Vikings way of not trying to adhere to history strictly and just tell a story loosely based on history and myth, then it'd have served it better...or at the very least serve the show better where there is much less breathing room compared to the books.
I don't see it as a problem. Uhtred contantly loses what he gains because he is a pagan, yet for a lot of the time he lived like a great lord, if not a king. His absence from history also comes from that.