Latos called out pretty much the entire team. Gray is calling out analytics and changes the coaching staff made him utilize, and has information to back it up. Bit of a difference there, IMO.
Also, where do you get the perception of hardheadedness? Gray has seemed interest and more than willing to make changes to improve himself. His issue was that the changes he made with the Yankees didn't help his performance. And as the article states, his slider was effective in terms of stats against it but it ignores the fact he struggled to throw it for strikes:
The athletic article goes into a lot of detail about the issues with the fastball. Gray doesn't have a fastball geared well to throw up in the zone, which is exactly where the Yankees were having him throw his fastball.As Gray notes, it wasn’t necessarily about the results with the slider, it was that the pitch put him in tough situations. That part is true. Gray threw his slider for balls more frequently with the Yankees. That may have led to Gray getting behind in more counts, which is never good for a pitcher.