100 ways to improve your writing - Gary Provost 2019

Avoid parentheses
Twelve ways to avoid making your reader hate you

Parentheses are used to enclose material that is not strictly necessary but rather serves as a comment on or a supplement to the main text. If you are using parentheses more than three times in a ten-page story, you are either interrupting the reader too much or you are using parentheses unnecessarily. The writer usually turns to parentheses out of laziness, not out of need, and there is usually an unobtrusive way to include the information without parentheses.

Mark Twain wrote, “A parenthesis is evidence that the man who uses it does not know how to write English or is too indolent to take the trouble to do it; . . . a man who will wantonly use a parenthesis will steal. For these reasons I am unfriendly to the parenthesis. When a man puts one into my mouth, his life is no longer safe.”

Twain, as you can see, didn’t much care for the parenthesis.

I wouldn’t say you should never use parentheses, but I think you should use them rarely.