He's been here 2 and a half years. The first year was stop/start with injuries, managerial change and he never found any form - nobody is arguing that he played well then. Since Emery came in, which is what, 18 months? He's been good, was improving and this season excellent. It's wrong to say that the majority of the time he's been here he's been 'pretty poor' - it's just demonstrably untrue.
I really don't understand why you have such a hard time admitting that you might have been wrong about a player. There is no shame in that. Doubling down, however, doesn't reflect well at all.