Honestly, the thing that bothers me the VERY MOST in the Jane Austen or any classic lit fandom is when someone says, "I'm really struggling reading these novels, it seems like a different type of English, any tips?" And there are always a few comments like:
I read these books in high school
This is the internet. They may not be a native English speaker. They may be one of the dozens of people who don't live in the US!
Yes, Jane Austen uses modern English, but she has a massive vocabulary, some words she uses have meaning drift or are out of fashion, and having a knowledge of British history can really help in understanding her texts
This is not the time to brag about your reading level in high school, you pretentious, precocious, know-it-all, prick! If you actually want people to read the classics maybe try helping them instead of making them feel like idiots
Helpful things to say would be:
It is hard, though it tends to get better once you get used to her writing style
Try watching an adaptation first or using an audio book, which can help you follow the story
Feel free to ask for help if you have difficulty with a particular passage (and then don't be a dick about it)
Try Northanger Abbey first, the language there is a bit easier
Once I watched Reddit assist a reader all the way through Emma as they struggled with passages and it was beautiful! Please do not shame people for asking for help or struggling! The community will only get smaller. This is not the place to brag about your freaking reading level in your youth