There's a big difference between copying conventions and literally copying the colour scheme/gradients. Many of your examples have the competitor creating a sl

There's a big difference between copying conventions and literally copying the colour scheme/gradients. Many of your examples have the competitor creating a slightly different style, be it button style or menus. Open Office/Microsoft Office. Windows versus MacOS. Hell, look at DuckDuckGo and Bing. Sure they are both search engines (just like Google) but they still have a slightly different visual identity and results page than Google. HN is very similar to Reddit but still tries to do small things that differentiate it. The original post looks like literal translation of Tumblr. Even if they changed the colors so that it fit with it's own identity I could agree with your point but this is not even close to being the case.