There are hundreds and thousands of perfectly fine free themes on the wordpress repository.
If I want to pay for a theme I would like it to be premium.
I was just scrolling through all the 500 premium themes on envator elements. I have yet to see 1 theme that I can recognise from my previous experience with themeforest.
I took 4 themes by random:
9, 152, 111 and 41 sales on themeforest
It just looks like there is little chance for me to find anything in the top 500 items at all that are in the list of available themes on elements.
Any author who has 9 sales on his/her theme will not afford to maintain that for more than 6 months, then th theme will be abandoned, so no updates.