It's not about being a ground instructor, it's having the confidence to do so. Yes, a line pilot may not need to be one, BUT, neither you, nor I, know where a career will take you. I intended to be a line airline pilot, I wound up being an instructor, an examiner, a commander during wars and now present my company's products in front of buyers. Not one of those outcomes was planned when i was your age. The more tools you have, the greater your opportunities. Luck is about preparation.

GF