ではあるんだろうが meaning

Question

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.

Answer 1

A very literal translation would be:

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。

(literal) Of course, it would be (like) "Because he is putting effort into basketball seriously", though.

→ Of course this is because he is devoting himself to basketball, though.

• ではある is a contrastive (は) version of である, which is a stiff version of だ. This is used to admit something while the actual message is something different. (E.g, Netflixは有料ではあるが素晴らしい "Netflix is wonderful, although (admittedly) there's a charge.") See: What is a good way to translate ではある?
• ん is so-called explanatory-no.
• だろう is for inference
• が is like "..., though".

Put together, ～ではあるんだろうが is like "although ～ should be the case", "But, well, it's at least true that ～", etc.