I have a suggestion for Envato - specifically for Wordpress themes which you sell on themeforest marketplace. Now as you are aware that after Wordpress 5.5 was released in August 2020, many themes with earlier code were not compatible. Now some authors have till date not updated their theme. How about you add a big banner stating that theme has not been updated and not compatible with latest wordpress version. That way new sales wont happen and hopefully authors will update their code to the latest version. Another point is some users may purchase incompatible theme and then face issues, so hope a warning like message to all themes not updated. And maybe extreme step like even removing the theme from the marketplace that way authors keep their themes with bundled plugins up to date. Just a suggestion.
I had put up this suggestion and even contacted Envato Support in this regard. Was told nothing can be done! Was told that theme compatibility is mentioned so we need to check and purchase. Now you will also agree that 2 years back the theme was compatible, but as Wordpress releases new versions its the responsibility of Envato and the theme developer to see that themes are kept compatibile with the latest version as there are security as well as compatibility fixes that are put by Wordpress. If the theme is no longer compatible, I really suggest that either the theme be removed till the developer fixes the issues (this will help buyers) as the developer will need to keep the theme compatible with the latest versions. Also a note stating that compatibility is not tested with latest version (just like Wordpress theme/plugin repository has) so user is aware that if they purchase a specific theme / plugin it may not be compatible. Also in the banner say if a theme has not been updated for long - theme/plugin has not been updated for past X or Y months or years so before purchasing user is aware of the status of the theme/plugin. I think this will help keep the envato marketplace compatible with the latest versions and fresh code too!