In my opinion, most elders do deserve basic respect from students and those younger than them. That is, only if they have either earned it by their words and actions then it is fair to treat them with respect.
However, if an adult is rude towards a younger person or even a bit condescending, I believe young adults have the right to reciprocate that energy they receive.
Most adults that I’ve spoken to so far expect those younger than them despite the way they treat them, which is not how you earn respect. I especially witnessed this with adults and teenagers.
Not everyone is obliged to respect an elder just because they think they’re older and considered “superior”. I don’t think age determines the amount of respect you’re supposed to have for someone else. Everyone gets what they deserve.
