もちろんバスケに対して真剣に取り組むからこそ、ではあるんだろうが。
Is there any specific meaning for ではあるんだろうが in this sentence?
The story was about the narrator's classmate, who was strict during the basketball practice and it seemed he (the classmate) was being hated by their underclassmen who joined in the basketball club. This classmate is striving to become a professional basketball player, that's why he takes basketball seriously ( as mentioned on バスケに対して真剣に取り組むからこそ).
Thank you for your kind guidance.