Mantha is starting to remind me of Semin a little bit. AS had a shitload of talent but seemed like he considered himself burdened by it. Like some 7-footers in basketball who just plod through games with zero joy. You can tell they were steered into the sport because of their natural gifts and the attention and money that came with it, and that's all.
I met Semin a few times at the big fan events. Super nice, but also obviously extremely introverted. He avoided attention and the press like the plague, and he seemed to struggle with the language more as a result. But if you followed him between seasons and when he left for the KHL he was no more apt to talk to the press than he was here. They labeled him a quiet leader. Our press had nothing to work with so they just filled in the blanks and he became Alex The Enigma.
So when the "We're going to build a 2nd line around Semin" era began and lasted for years because GMGM couldn't find a 2C to save his life, Semin checked out. He had every right to be frustrated. He was a creative genius with the puck playing with linemates that couldn't keep up. His attitude left a lot to be desired for sure, but there's nothing enigmatic about a guy who's frustrated for reasons that are plain as day.
We tell a similar story in DC about Jagr; that those were just the years he decided to play worse. And just like Semin, while there's certainly some truth there with regard to his attitude, we also did jack shit to cater to or seriously leverage his abilities. Both guys struggled here for plenty of valid reasons. Attitude and drive were definitely part of it, but giving them more to work with would have helped.
So if Mantha is jaded for similar reasons, he should get over it because he doesn't have the skills to make dealing with this shit worth it. The similarities end with his ceiling.