Like I wouldn't call them useless because if they were useless they would have no impact on the show or the contestants. They are there more to tear down and break the confidence of trainees.
Compare this to Produce 48, the trainers were so much better. Soyou and Hongki despite being harsh, were more encouraging and has shown to help them more. You don't see them overly criticising what the trainees did wrong, rather they give opinion and feedback on how they can do better.
Even our scary Bae Yoon Jung who is known to be super intimidating, is more loving and encouraging then the current masters.
Their critics are also so dumb and inconsistent. Remember when Bora slayed the high note in The Fifth Season? The master went like 'you didn't do as well as I expected', but when Jiyoon failed the high note they went like 'don't let a fail attempt determine your abilities' like erm ok.
The previous trainees were strict and critical, but at the same time encouraging and give constructive comments. The current masters are just saying everything they don't like and tear down the trainees and be like 'if you can't do better you are going home'
Calling them masters is such an insult. Master? More like masters of manipulation and masters of confidence destroyers.