Address it. If online students are being disadvantaged by staff not making their class accessible then it is their responsibility to raise the issue. If you don't want to speak directly to her, then there should be someone at the school that you speak to who can raise it on your behalf. I don't know how the chain of command works in your school system so don't know the exact terminology, but there should be someone or multiple people at the school you (or your entire class/year group) are assigned to that you can speak to about any concerns you have. We use terms such as 'tutor', 'guidance councillor', 'head of year', etc here. I'm in a position where I liase between staff and students to communicate things they're unhappy with, and it does get results.
Also, side note. If it bothers you that you feel as if you have to leave birthday messages for every single person every day and you want to lift this burden - from a Rules & Guidelines perspective it is close to bordering on spam.
It may just take them some time to adjust. It is a big thing to throw at them, and not everybody takes change well - especially when it's something they don't fully understand. Failing that, life is too short to invest it in people who can't respect you. Make a new family by surrounding yourself with people who genuinely love and care for you. I cut off a number of my blood relatives in the past year and a half because they couldn't respect my gender/sexuality, but I've filled those spaces with people who are prepared to raise hell and fight to defend my rights.
This isn't going to be what you want to hear, but I feel it might help you to hear it: this is exactly the mindset your teacher was trying to prevent you falling into by discouraging students from sharing their ages in the first place.
This classroom environment you have described is representative of what higher education and the working world looks like. It looks like your teacher is trying to teach you about professional respect - and the sooner you get your head around it the easier the rest of your life will be. The real world isn't categorised by age groups, and it's a hard mindset for some people to shake when they leave school. You are likely to have colleagues of vastly different ages to you and you will be expected to treat each other as equals regardless of your respective ages. Someone significantly younger than you may even be your superior. The people who thrive and make the best colleagues are the ones who are friendly and supportive towards everyone and don't let differences such as age (or gender, race, sexuality, disability, etc) influence how they think of and interact with people.
Social science classes, such as philosophy, tend to encourage lots of class discussion because being able to critically analyse and debate is a required skill in that field. My ex had a PhD in philosophy and would say that his job was to argue for a living. On days he taught undergrads at the university, he'd complain about the classes that were quiet and rave about the ones that actually spoke up. If this isn't something you enjoy, then maybe the social sciences aren't a good fit for you. You compared your philosophy class to your marine class, and the difference you're observing is more likely to do with the field rather than the specific teacher or the ages of your peers. Science classes will have some discussion, but not nearly to the same extent as social science classes. In science classes at university level, often the lecturer has a lot of complex content to cover and not a lot of time to do it, so they might even need to cut off conversation so that they can get through the rest of the material in time. (For context, I'm both a scientist and a current postgrad student.)
Being talkative isn't a trait of younger people - it's a defining trait of extroverts in general. And you're always going to encounter them in life. Back when I worked in an office the biggest chatterbox was a woman in her late 30s who worked in HR. She was perfectly professional on the phone, then she'd slam it down and call the customer a ****. We knew her whole life, because she never shut up. It could be very frustrating when you were trying to analyse complex data and all you could hear was her voice. But she was adored and easily one of the most liked people in a company with ~70 employees. She went above and beyond for us and was always the first one there with a cup of tea and a hug when you were having a bad day.
Maybe I've just wasted my time breaking this down, but I hope some of it might get through. I'm in the same boat as you, in that I'm 5-7yrs older than the majority of my current colleagues, and it requires some patience at times (especially when there's social drama I'm expected to mediate) but ultimately it doesn't matter all that much. What matters isn't a person's age but what they bring to the table and their outlook. I am not the most intelligent person, but I thrive in the classroom and workplace based on social skills. I'm well-liked and get along with everyone on both a personal and professional level, and I put that down to being friendly and treating everyone as my equal - they even elected me as their representative. The person I get along with best is actually 7yrs my junior - she's a good listener, gives fantastic advice, and doesn't hesitate to call me out when she thinks I'm being dumb or harsh. She's become the person I go to when I need advice on how to handle an issue, because I know she'll give it to me straight (although she does make jabs about me being old).
i think my teeth are getting super sensitive
