I'm not exactly sure what you wanted to see from a player working with the 2nd and 3rd team offense, vanilla play calls. That said, he had a 22-yard TD and he caught 64% of his passes and did a jet sweep, worked out of the backfield. That's how he should be used, all over the place.
I want to see something. Guys like Jarret Boykin, Jeff Janis, Ruvell Martin etc all looked like they had something in the preseason. They made themselves be noticed. You have taken the position that Rodgers and Cobb are keeping Amari down. Well they weren't around and if a guy like Boykin can make a team playing with 2nd and 3rd string vanilla offenses against the same in the preseason, I'd expect to see a little more from Amari. He didn't exactly jump out and show how much he's changed.
I thought it was just a confidence issue last year. And it resulted in tentative running, muffed punts/kicks, indecision and overall slow play. I think he has the build and skill set to be a good player. But this latest bit makes me think the indecision, wrong routes, etc aren't from lack of confidence, but rather from lack of putting in the work. Success in the NFL is usually for the guys that get the little things, maybe Amari isn't putting in the work to learn the little things.
i know guys like Doubs and Watson aren't finished products and I can guarantee they still screw up on the field and in practice and yet Rodgers still has their backs. Probably because they're putting in the effort, asking questions, watching film and trying to get better. He backed MVS and guys like EQ who never really did anything for us. Likely for the same reasons, despite deficits they worked hard.
I don't think ARodgers would ever call someone out like that for talent reasons, but if 2 preseasons in and someone still hasn't gotten the message that it's a lot more than working out in a gym and showing up to practice, it's time to get that message or he'll be out. and it won't be because of Rodgers and Cobb, it will be because of Amari.