Using an occasional archaic word can give your stories a distinctive "feel". I think some readers, at least, will enjoy occasionally learning a new word.
But I can think of two big reasons to limit this.
One, while YOU might use archaic words, would your characters? If you have a character who is a literature professor and in dialog he uses words like "cozen" and "abjure", okay, not implausible. But if you have a tough street gang member using such words ... that would just sound very implausible. You might justify it, but you can't just throw it in.
Two, if you use too many archaic words, the reader is going to find your text incomprehensible. To some extent you can avoid or reduce the problem by giving a hint of the meeting in context. Like if you write, "He stabbed his victim with a sharp bodkin", the reader can readily guess that a "bodkin" must be some kind of knife or sword. But, "He opened the box and was surprised to see a carcanet inside" ... well that could be anything. But in general, if you use one word that is likely to be unfamiliar to the reader every few pages, it can be interesting. But ten per sentence and you might as well be writing in a foreign language.
As a special case, if you are writing historical fiction, a certain amount of archaic words are expected and help to set the tone. I think it would break the feel of a book set in ancient Rome if a character says, "Oh no, Publius has Hansen's disease!" If I was writing such a story, I'd have the character say that he has "leprosy". One could quibble that presumably the characters are speaking Latin and the English is a translation, so why shouldn't we translate into 21st century English rather than 19th century English? But it just ... feels wrong.