Oh Lord, it is. It's actually the same for any language I know of.
Note, that we are talking about one particular meaning of the word dialect: "a form of a language spoken by members of a particular social class or occupational group, distinguished by its vocabulary, grammar, and pronunciation" (Collins dictionary). Hence, in Italian, dialect would be translated with two different words:
dialect n (language: local variation) dialetto nm
dialect n (specialized language, jargon) gergo nm
Partially, language of a particular social group is connected with jargon. It's impossible to imagine that financial planners in their annual reports would use the same words as the YouTube commentators or, on the contrary, that somebody would use financial terms for chatting in social networks.
But beside jargon (i.e., characteristic vocabulary of a special activity, occupational or social group), there are also the questions of specific style of writing, goals and tasks, audience, presentation of facts, ideas, and conclusions.
The commentators on YouTube (or any other social network) use mainly youth jargon, consisting of exclamations and often truncated words (compare: "u" instead of "you", "cmq" instead of "comunque").
The (crime) novelists have to imitate varieties of speech for each and every personage, depending on his/her social status, occupation, provenance, age, gender, etc. Just as a successful trader from Wall Street in a novel speaks differently from a waitress, a banker from Milan doesn't speak the same language as a waitress from Milan.
Yet another story is journalist language. It often seems to be "plain" and "simple," but it has to follow a lot of very specific style rules and is studied in details at various university programs.
Financial and/or legal language ought to be very precise, excessively precise. It's one of the reasons, why one needs a special education just to understand bank reports or juridical decisions, leaving apart writing them.
And, of course, scientific language is not similar to any of them. It has to be precise in terms of methodology, terms, and formulas, yet very careful in conclusions and formalities. Scientific language (be it English or Italian, in physics or medicine) is famous for excessive use of passive voice, citations, and long phrases that nobody is able to understand after the first reading.