Sophisticated / Intellectual Japanese?

In English, there are certain ways of speaking which are perceived differently. For example, clear or old-fashioned English seems to have a better reputation than the Redneck English of backwater Americans. "Older" language, it seems to me, is more often used in intellectual or even posh circles, while you can get more and more modern as ypu het more casual.
My question is: Does Japanese have anything similar? Is older Japanase, say, from the 30s, even understood, and do certain regional accents, like in Ōsaka, have some kind of reputation? How do I distinguish between what's perceived as casual and what's perceived as sophisticated?

I'm not well versed enough to go into details, but Japanese has MANY different levels of speech. More than English has, for sure. Formal, polite, casual, practically rude... Changing a single word can affect which category it falls into.

One point among many: full-kanji, on-yomi words often have the same air as Latin-origin words do in English. For example saying 飲料 instead of 飲み物 is like saying "a beverage" instead of "a drink".

first of all, you should think separately regional dialects and many different expressions (like formal, polite, respect, modesty, etc.).
we change words and expressions depending on conversational partners and occasions.
actually, our sophistication and intelligence are judged by how many words and expressions we know and that we can use them properly. also, by beautiful handwriting of Japanese.

The following website will be a very good place to start for you.
https://en.wikipedia.org/wiki/Japanese_language#Vocabulary

Thank you very much for the answers! But still, I'm afraid my question remains a bit open. I am familiar with the language and I do speak it, though not fluently, thus I am familiar with politeness levels, different levels and similar. The answers concerning Kango words were more helpful, what I want to know is nuances outside of politeness. As I described, in English, there are certain ways of speaking, regardless of formality, that appear sophisticated, rural or are associated to something else. Is there a similar "Sophisticated Japanese"?

Does Japanese have anything similar?

Yes.

Is older Japanase, say, from the 30s, even understood,

Do you mean 1930s? Of course it is understood, just as English that old is. But of course, certain words do change. For example, the majority of the Japanese in their twenties may not know words like "sato" instead of "jikka", "kawaya" or "habakari" instead of "benjo" etc.

and do certain regional accents, like in Ōsaka, have some kind of reputation?

There are stereotypes, just as there are for Texas accents or Manchester accents.

How do I distinguish between what's perceived as casual and what's perceived as sophisticated?

This is a question I don't understand. "Casual" is not the opposite of "sophisticated", at least not in Britain, U.S. and Japan. That said, I think that any person with proper knowledge of keigo can distinguish "casual" if it were in either hyojungo or Tokyo-ben. As for dialects, you cannot distinguish "casual" or "sophisticated" unless you have knowledge of that dialect to a certain extent.

Speaking of Osaka, many people may have the stereotype of Osaka-ben being comical, but Junichiro Tanizaki has written a lot of novels on sophisticated Osakans who speak sophistiated Osaka-ben.

By the way, "sophisticated" and "rural" aren't opposites either, at least not in Britain, U.S. and Japan. I wonder if you want to distinguish "uneducated".

Thank you very much. The reason for this question was rather about stereotypes and how they would speak in, say, a story: What would some rich, posh person sound like, how would very old people speak, what vocabulary does the youth rather use and what kind of speech would rather be associated with Rock-loving local mechanic? What's the difference between the friendly chatter between farmers and an intellectual discussion between professors of a university? Sorry, I might've been unclear before. English isn't my mother language, maybe "sophisticated" was the wrong word. I hope it has become understandable now.

Yes, that exists in Japanese language too.

For example, when you are goint to eat something,
when you are talking with the intimate person.
Can I eat this one? 　Kore tabete ii?
in the polite style,
May I have this one? Kore wo Itadaitemo yoi de shouka?
more polite style,
Is it possible for me to have this one? Kore wo Ittadakutoiu kotoha kanou desuka?
more polite style,
Do you mind my having this one? Okini sawaranaito iidesuga, korewo itadaku kotoha
dekimasuka?

It might be same in English, when you want to say it in polite style.