Actually yunjin stan write on pannchoa;
Its because of the misunderstanding that Yunjin was trained in opera. It takes university level education at a conservatoire and years of being an understudy before someone can be considered an opera singer (the decline in skill in opera being a discussion for another time).
What Yunjin did study was classical singing, but she never achieved anything above a chamber choir level. For her age, she was quite good, but she became a trainee before she had the chance to fully develop her voice. I doubt Pledis had the necessary staff to help her develop her singing. She lacks a strong middle and chest voice which leads her to sound very shrill. She also never developed the muscles (glottal) that are needed to produce a belting sound. So she ends up pushing her voice out using her throat which will cause damage to her vocal cords.
Her pitch has also wildly deteriorated, probably from years of sitting in Pledis' basement without having a chance to train her ear and run scales with a proper voice teacher. I watched HYBE's documentary and their vocal team suck and give meaningless advice, so she's not getting much support there. She only really knows how to sing in head voice, but because the other parts of her voice are so underdeveloped the sound ends up sounding thin, shrill, and grating. Its actually really sad because its obvious she loves singing and wants to be able to do it well, but she doesn't have the opportunity to learn.
Classical singing and pop singing aren't actually that different. With the latter being derived from classical singing and jazz. Beyonce, Whitney Houston, Frank Sinatra are just a few examples of those trained with a classical foundation who sang pop. Eunji is also a good example of K-Pop singer with a classical foundation who is a free, bright, open and strong sound throughout her entire voice.
Sorry for the long comment. I thought I'd offer some explanation because I really like her and it saddens me she's not getting the chance to fulfil her potential.
No, they're right. She can't be considered an opera singer. What she was, was someone on the beginnings of a career towards opera. (Though iirc, her aim was Broadway not actually Opera, but with an inclination towards productions like Les Mis and Phantom). She was singing with a classical foundation that was still developing, but she stopped before she had the chance to actually develop her skills properly. Opera requires university level education at a conservatoire, understudy work, and sometimes even post-graduate training. That's about 15 years of study before you even have the chance to hit the board
