Well feels ironic, but we have often played very good attacking football with him (not because him mostly, but still). Under LVG he started in our best 4 match run when we beat Spurs, Liverpool and City playing very good football. Under Mourinho he started the 2017/2018 season and we scored and kepts clean sheets for fun with him and Bailly. Also started in the run under Ole when we won many games and scored a lot.
He has been injured a lot, but when played regulary we have often done well. Then he has some terrible games too.
Was decent also for Moyes as a DM and for SAF as RB when we scored a lot, but don't think he got the legs for those roles anymore.
People underrate what he has done, but also not sure he got it in him anymore to find good form. His fitness is just a joke and I think he is slower now than before.
So we should have let him go. If he proves himself in training though and stay fit he could be good to have still.
Problem with Jones is that he is not the most clever defender. He needed his physical qualities to perform.
Just like Bailly and Rojo too I may add.