But Lou...
He's not actually 'had a pop' at all.
Whenever he 'criticised' Ross, in the first half of the season, he did it at the same time as criticising all of the squad for not having enough attacking 'productivity', as he calls it. This is after making him captain for a game.
Then, when asked about the contract, he stated that Ross would be/had been offered a good deal but if he didn't sign we may have to sell, as the contract situation deemed it so. He's consistently also said 'we want to keep our best players'.
That's not having a pop.
Koeman rates Ross and Ross has worked hard to prove he can work under Koeman. He improved a lot from Xmas onwards last year. But still, 5 goals and 9 assists in all competitions isn't staggering is it? We need more, and Koeman said he'd be targeting the forward area.
But he hasn't signed a mega deal for this club. That's, at the end of the day, nobody else's decision except Ross.