This might be controversial but I will try my best to explain my reasoning. What I mean is that they shouldn't be themselves when they are on the job.

Being an idol is a job, and a big part of that job is selling personalities. In real life, I'm sure most people act differently when they are at work compared to when they are with friends, family etc. and it's not "fake" to do so. It's pretty much just knowing your audience and knowing what they want. Introverts may push themselves to act extroverted and loud to gain attention, cocky people night act humble, people who might be assholes hide behind a friendly persona. It's all part of an idols job. From a business standpoint, it's what gains fans and earns them money. I don't think it's "inhumane" for idols to act differently than they would off-cam for their job, I think it's being professional.

Another thing is, call me cynical but I feel like if idols were to be 100% themselves on camera, we would be severely disappointed. This is just me being cynical again but I feel that if idols were completely themselves on camera, a lot idols would probably be outed for being ignorant, bad people or just any other negative attribute (which I know is part of normal human behavior). I think fans forget that all idols filter themselves for how they appear on camera, the only difference is how much they filter. Think about all the idols who got outed for being bad people and how it would've been obvious had they not had to put on a persona for the camera. I know they might be the exception to the rule, but I also think there are probably more bad people in the industry than we expect.

Because of this, I can understand why many idols aren't allowed to have their own social media or are kept on a short leash in general. While socmed can be a platform for them to spread positivity, connect with fans etc. I think the vice versa is also true. Since idols live in a bubble, it's safe to say some of them are ignorant (if the constant cries of cultural appropriation by fans is evident) and giving them free reign of their socmed is just giving them the freedom to make themselves look dumb/ignorant (which some idols have done before) IF they are either of these things. I'm not saying they should never have their own socmed accounts, but personally I believe it's better to use an official account managed by the company for the first few years until they've proven they can be smart about how they use their socmed.

TL;DR I oppose people saying that idols should be themselves on camera, and think that then putting on a persona/being filtered is the right choice.