Comparing Gwern's to your website is really interesting. I'd argue, Gwern's website is a good example of minimalist design, whereas the website you posted is the opposite.
To me, minimalist design is as little design as possible (Dieter Rams). All design elements need to serve and enhance usability/functionality of the product. That doesn't mean that the total functionality of something needs to be minimal. E.g. you can still have tags, recommended articles and a comment section.
In the website you posted, I see design elements that don't serve the usability of the website, but are there just for design sake. E.g. the background image, the colour of the toolbar or the right alignment of the text
To me, minimalist design is as little design as possible (Dieter Rams). All design elements need to serve and enhance usability/functionality of the product. That doesn't mean that the total functionality of something needs to be minimal. E.g. you can still have tags, recommended articles and a comment section.
In the website you posted, I see design elements that don't serve the usability of the website, but are there just for design sake. E.g. the background image, the colour of the toolbar or the right alignment of the text