Is This The Real Reason Why Leroy Sane Was Dropped From Germany's Squad?

Germany manager Joachim Low has opted to leave PFA Young Player of the Year and Premier League winner Leroy Sane out of his 23-man squad and as a result, the football world has reacted accordingly.
Sane, who was prolific for Manchester City under Pep Guardiola this season, was a strong favourite to be included in a Germany’s side set to conquer the World Cup later this month.

But it seems Bayer Leverkusen winger Julian Brandt beat him to a place on the plane, but it there another reason behind his omission?

It was originally reported that it was a very close call between Sane and Brandt, along with a number of others, but a report has emerged surrounding his attitude in the Germany camp.
Apparently Sane’s ‘big-time attitude’ was a factor behind the decision.
The 22-year-old’s behaviour around the camp was a ‘major factor’ claim The Sun, and manager Low didn’t want to risk upsetting other members of the squad by picking the Manchester City winger.
“A change in his attitude was noticed in team meetings and around the German camp.” the report states.
Shortly after his team was announced, Joachim Low explained his reasoning behind the somewhat controversial decision:
“That was a very close decision between him and Julian Brandt, which was made in favor of Brandt, Draxler Reus and Müller are set. Leroy has a huge talent.
“He will be back again from September. He had not arrived in international matches yet.”
TheSun.com