If you think 'free software has poor usability' you've never tried commercial software.
(side note: I might have accidentally down-voted you as my hand brushed over the screen. If so, I apologize and hopefully someone will give you an up-vote for me to replace it.)
Now, for truly horrific usability, nothing beats enterprise software with those big money support contracts. Very much like American car companies in the 1970 / 80s which viewed service as a profit center.