Yaoi is a genre of Japanese manga, anime, and other media that focuses on romantic relationships between male characters. Therefore, it should be correct to be a tag
No, Since you’ve heard that yaoi originated from Japan, it doesn’t make sense that you know nothing about bara. bara can completely replace yaoi, bara can be romantic. Yaoi only refers to BL/Feminine works（almost an antonym of bara.）. so yaoi tag is redundant. Some people like to confuse the original meaning of a word (Like ehentai Only yaoi, no bara. or like Straight yaoi, straight bara. which is pretty disgusting), which is meaningless. Tags need to be accurate