He isn't that good. There are few european coaches that stated publicly they wouldn't want him on their team(addition by subtraction) since he doesn't play defense and is too ball dominant. Olympiacos won two straight euroleagues after he left.
that's the problem with euro (and some nba) players *cough* spanoulis *cough*, they need the offense to be based around them but they're not good enough for that to make sense.
It depends on the intelligence of the player. Spanoulis wasn't even a very good European player when he moved to the US. Although he wanted to play 30 minutes a game with limited skill set. Scola was a top 5 Euroleague player when the Rockets signed him. But, even so, he barely played for 3 months. He worked hard for his spot and at the end he become a very good 2nd/3rd option in the NBA.
^^^ Is there a difference in the NBA vs the Euroleague? In the Euroleague they allow tip ins even in circumstances that would be goal interference in the NBA. Scola was a high jumper but was good at getting to the rim and I noticed him tip the ball in quit a lot back in the late 2000s to get some those points.
I'm excited until I see his advanced stats in recent years(hint: not what you would expect from a top Euroleague player).
I love him on offense, he scores and creates for others, but Kyrie went off against him without any resistance or attempt to foul at all.