In creative circles, there is an ongoing debate about which online platform is best for selling patterns: Etsy or Ravelry. And more sites are regularly coming online to also try to grab a piece of the action, such as Ribblr, LoveCrafts, Ko-fi, and more.
As a pattern designer, I have used both Etsy and Ravelry to sell patterns, so I can speak to this debate from the viewpoint of having used both.
Etsy charges sellers a fee for their listings (and the listings expire and have to be renewed every X number of days, which means you pay the listing fee again) whether you sell anything or not. Ravelry doesn't charge listing fees, and your listings never expire; it only charges you a fee when you make a sale. Depending on your individual needs and goals, there are different advantages and disadvantages to each platform, so the answer of which platform is best is entirely dependent upon your particular situation. There is no one-size-fits-all best answer.