*Cracks knuckles and puts on glasses at his typewriter*
Let me be clear, I'm not arguing against transparency or showing what you're getting for your money. They hire agencies because it would become a full-time job if you were as big as some of these girls are. Same reason that actors and athletes have agencies. They care about profitability, not morals on a site selling sex.
However, It's not about "being bad at it". It's just simply understanding the way this industry works with parasocial relationships. No preview = mystery. Mystery = you wanting to see what's behind the curtain. If you want it bad enough, you'll buy it if you're too impulsive to wait on a leak somewhere. This strategy, however, has diminishing returns (just look at Amouranth over time).
It's all a mind game. It's all about the fantasy it sells. The same reason "idols" in Asian countries hide their relationship status. It's why you don't see women in the sex industry with wedding rings on. There is data all over the place to prove that hiding your private details sells more sex because simps think you're available and that there's "a chance to be noticed". Hiding the fact that you're not talking to them directly is the same thing. OF girls also vaguely say that "they" (the royal 'they', i.e. their agency) answer people in DMs (because tons of tipping happens there).
Becoming an OF girl already damages the image she's cultivated up to this point. She called it "empowering", but anyone with a brain knows that's bullshit. That's irreversible at this point. It's associated with her name. The issue she's likely to run into is that she's trying to stay in that middle ground where she's not selling nudes, but she's also not fully SFW. That works for some creators and sullies others. Only time will tell.
TL;DR - Most girls won't say when they're married or have a partner because it breaks the illusion for some that would otherwise pay to goon to them. It's not a grand conspiracy. It's why she said OF is for "videos too spicy for YouTube" but she'll never say that she will/won't go nude because she wants to keep that gooner audience.