Not sure what's happening here, I don't read Korean. But if a manager is forbidding Irene to have photos or props, then I think that manager or those managers if it's more than 1 are going too far: at this point the RV members have been in the business for more than 10 years, they're grown adults and some even in their '30s, they can decide for themselves what they want to do when and don't deserve to be treated as kids who're not allowed to have their own opinion and freedom.
As for the mistreating, I don't know if Irene is treated worse than the others or not. But seeing how she just had her solo debut and will have her sub-unit comeback with Seulgi in a few months, I'd say that she's getting proper attention and resources from the company.
If anything, I'd say that it's Joy and especially Yeri are being neglected or forgotten when it comes to personal opportunities and promotion.
Yeri has acting gigs. That's why she's participating less in SMTown than everyone not named Wendy. Joy must be content with whatever she was offered, considering she renewed.