The online etymology  tells us:

1733, "an admirer of a fine art, literature, science, etc., one who cultivates an art or literature casually and for amusement," a borrowing of Italian dilettante "lover of music or painting," from dilettare "to delight," from Latin delectare "to allure, delight, charm, please,"

Originally without negative connotation, "devoted amateur;" the pejorative sense "superficial and affected dabbler" emerged late 18c. by contrast with professional.

Don't laugh, Seeing Myrs' entry, then shaking off the dizziness it caused, my first thought was a prone, scantilly clad twirling dervish like painter??

My second thought and yes, I have used the word to describe a few people in my life. Was, ' A Jack of All Trades, Master of None ', at no time was it used as an insult, rather as a compliment on their varied and much needed skills at the time.

That my friends was two cents worth,