How often do you now use these features of English which are disappearing?

My husband actually got in trouble at work because his notes had too many ‘big words’ in…he has a degree in English and creative writing and is a published poet… He doesn’t tend to use that language in speech especially anymore because people don’t understand and in professional environments find it pretentious and patronising almost… I sometimes find it difficult to interpret the complexities of his writing, whether it is a creative piece or not…I studied Law at degree, which uses such antiquated language and I still struggle lol Maybe it is the rise of things like tik-tok and snap chat too…we have 3 sons aged 11, 13 and 17…they are always using slang that they’ve picked up there or in high school…they are more likely to interact with these platforms than they are to read a book…especially an old classic which might include those features of writing… I wouldn’t use it in everyday speech but I always use it in written communication ‘To whom it may concern’ is one of my faves…I write a lot of those letters and emails, due to having a special needs child, who is fortunate (or unfortunate - depending on which way you look at it) enough to just about cope in mainstream school, with a lot of support… It must be unusual because the staff always seem taken aback by my emails, like they don’t expect parents to be so well educated, or spoken!!