Hi Ellen,
Your questions are totally reasonable, and let me give you my initial thoughts on the three examples you discussed.
1.) The woman who was hemming-and-hawing about her white privilege was, unfortunately, engaging in virtue signaling and performative allyship. She was turning something not at all about race INTO a soliloquy about race. Her orthodontal problems had nothing to do with her being White.
I mean, I can admit that I possess white privilege -- but if I were to verbally flog myself for being White, that doesn't do anything to erase the fact that I have autism. And my autism isn't the reason for systemic, social, and cultural forms of racism. Me acknowledging or denying/hiding my autism doesn't do anything to strengthen my ability to help uplift Black, Asian, Latino, or Indigenous people. So, in that same vein...whether she gets all of her teeth replaced with dentures, or knocks all of her teeth out and sucks everything through a straw for the rest of her life...neither scenario will move the needle in terms of race relations, one way or the other.
2.) I don't know Naomi Osaka personally...but, as someone with mental health issues myself, my CONJECTURE is that she may have simply been triggered in that moment...possibly due to tangential thoughts she was having about her personal stressors. That doesn't mean it was necessarily the reporter's fault...it means that people with disabilities need greater support from society as a whole. Her abrupt departure from the interview was a testament to that.
3.) You identifying as a woman, while also being a cisgender person...and a trans woman identifying as a woman when she is simultaneously a transgender person...those aren't mutually-exclusive realities. You identifying as a woman doesn't take away from (or infringe upon) her identification as a woman. Both you and she are entitled to sovereignty over your sex lives and bodily autonomy...as are transgender men and cisgender men.
Those are my thoughts. You shouldn't feel self-conscious or embarrassed to be raising these issues. People of all backgrounds should appreciate your willingness to be raw and authentic about your emotions and sentiments.