Not exactly, it's only like this because the plot is about nobility and romance and harem and shit like that. There are some other time isekai that I've read that do not have anything related to the typical nobles and harem trope, it's just that this characteristics and scenes are very popular right now.
Sometimes people just dream to live in these eras or worlds lol.
uhmm i think its because historically speaking these events are actually very common in the past? like these banquets are their only means of social interaction back in the day. its not like people can interact with social media before. and without any interactions with the characters, the story couldn't progress. so yeah
I wonder if it's necessary for every otome Isekai to have dramas in banquet/ ballroom/ dining hall etc? Is this what most women fantasize? Although I am one, I genuinely cannot relate.
EDIT1: Thanks for the insightful replies you wonderful people!
EDIT2: Oh shit. All the comments just disappeared. I'm so dumb totally not the right place to collect survey