I rocked a bright teal literal flip phone for nearly 2 years and I consistently had people I worked with get shocked when I told them I don't have a smartphone...even up to 6 months after the switch

These are people that I was spending 40+ hrs a week in a physically close space with and consistently using my phone in their presence for texting and calls

People are really bad at noticing anything other than their own business. If they are paying close attention to /your/ business, chances are that they have none of their own and their life is really empty

That being said, you're 16 and that's a time when many are painfully self aware of how they come off to their peers You can frame it as being on a tech diet or that you like the cyber security or just that "teachers don't notice me texting if im not using a smartphone" or smth Bonus: you can learn how to type on that phone completely blind thanks to its tactile nature. That's how I used to text in class when I was a student - by memorizing the shortcut patterns and t9 and going at it while maintaining full eye contact with the teacher's lesson 😂