There was talk of 20m this summer, if I remember correctly. With no takers. So that could make sense.
I remember when we were discussing midfield options this spring, I did a stats package on a number of players, including him. It didn't look bad, but his contributions did come across as somewhat limited in scope. Really little to no input in offensive categories. Passing accuracy same as McTominay. His strongest area was in progressive passing, where his stats were really good. Good on pressing too. Tackles and interceptions, ball involvement (ie, Touches) and progressive carries, middle of the road (among the players I looked at). All in all, measured against the other players I looked at (Camavinga, Kessie, Locatelli, Rice, Neves, Llorente, Bissouma, Bentancur, Tchouameni, Merino, Phillips, Brozovic), he seemed like one of the least attractive options. But I suppose it depends what you're looking for. And at that price, maybe there's a case he'd be a useful piece. But the counterquestion would be, does he have enough overall quality.
Huge caveat; not really seen him play anywhere enough to form an opinion based on eye test.