I think the opposite, used to sell loads but got fed up of the time taken to list items, have to go to post offices to get proof of postage etc.

now I can list things in less than a minute with the app, and the simple delivery with QR codes and lockers makes posting it so much easier not having to go to a post office ( I drop loads off at midnight at the locker near me )

what are you finding complex?  if I'm listing something I search recently sold items for the same thing, select "sell one like this", take a photo , put a price on and list it , only takes a fraction of the time it used to.