In most cases, minimalist design (flat colours and shapes, simplistic fonts, etc.) looks extremely ugly, in my opinion. It's boring, bland, and soulless.
That doesn't mean minimalism is entirely bad, though. Some companies do it right, like Discord and Google. Some companies, however, do it in the worst way possible, like Microsoft with their godawful "Microsoft Design Language", and Reddit with the New Reddit theme. Minimalism is very easy to do, but very hard to do correctly.
Feel free to share your own opinions on minimalist design in this thread.
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