With respect, there is only so much that envato can and should do to add further clarity to the file type.
- categorise items by things like WP, HTML, Joomla, Tumblr etc.
- this category is again referenced on the item page itself
- different types priced differently
- provide item comments where buyers can sense check answers to questions with the author
If a buyer is still confused after all of that then it is unlikely that there is much else they could do to change that.
What else would you recommend to be clearer?
In your case - If you are not comfortable with HTML then the best suggestion would be to try and find a different item which is definitely a WP theme. This is a link to “news” type WP themes https://themeforest.net/category/wordpress/blog-magazine/news-editorial
It’s worth mentioning that while WP does not necessarily require any coding expertise, a degree of technical savviness is often required, especially with the advanced and extensive news type themes that contain a multitude of features and functionality.
You can try requesting a refund but technically mistaken purchases are not guaranteed grounds for it to be approved.