A big display of of knowing obscure facts and details….
There’s nothing wrong with focusing on the details, but someone who is pedantic makes a big display of knowing obscure facts and details.
Pedantic means “like a pedant,” someone who’s too concerned with literal accuracy or formality. It’s a negative term that implies someone is showing off book learning or trivia, especially in a tiresome way. You don’t want to go antique-shopping with a pedantic friend, who will use the opportunity to bore you with his in-depth knowledge of Chinese porcelain kitty-litter boxes.
Thanks to Vocabulary.com